Tire sizing to rim...something seems wrong.

[Kenny'sID]

This might go better with bicycle forum but since I'm registered here, I'll give it a shot. The tire on my ebike trailer is shot due to my spare cheap ebay tube popping immediately after replacing it on the road, and my having to drive it with no air to get home (that's mostly a warning about the cheapest ebay tubes, as two out of 4 popped, or actually split with an unreparable gash. So any recommendation on brand of reasonably priced good tube would be helpful here as well.

Anyway the tire says it's a 16x2.125, however, the full tire only measures 15 inches tops from top to bottom in inflated condition. This trailer was such a cheap setup to begin with, I question anything that doesn't seem right. So does that sound right to you? And if so, an explanation on how they come to that size would help for future reference. Thanks.

 

[MadRhino]

16 inch rims do vary a lot in actual size, from 315 mm to 350 mm if my old memory is still good. They are used from cheap plastic kid bikes to high end recumbent trikes, so they also vary a lot in quality.

16 inch in bicycle standards, does mean the tire mounted on the rim will end up with about 16 inch diameter. The result could be 15 or 17, according to the rim and tire choice.

Good tubes are not cheap, but they are well worth the price that you pay for them. I believe that you had a taste of why already. :wink:

 

[Kenny'sID]

Thanks MR, that helps considerably, Still doesn't make a lot of sense the way they size them, but that isn't your fault.

If I could buy locally no problem, just take the rim, but since I have to order the tire, I'll give it a few days for more advice then just go for it.

Yes, the popped tire was just the start of my problem on her maiden journey of 12 mile round trip to the grocery store, but I'll not buy cheap again. Battery went dead...still haven't figured that out, I mean only 4 miles of juice from an 18Ah battery? (4x12v 18ah sla's) that doesn't sound right. But no problem, got a gas backup, at least until the chain came of and got between the sprocket and the spokes putting an end to spokes hence the trip and with all those perishables. Thank goodness for good people that loaded me up pretty much immediately, and got myself, trailer and bike to my home. Whew!

 

[amberwolf]

Perhaps you could post a build thread for your setup, with complete details, pics uploaded in the posts, etc., and we could give you suggestions of what to improve and where/how, for reliability.

Quite a few of us use our bikes for cargo hauling in various conditions, and could help you get set up for never having to worry about that sort of thing again.

 

[dogman dan]

Re tubes,, I pretty much will only run bottranger brand thick tubes from a local bike shop.

Why those? Mostly because the bike shop turns its stock, and the tubes are always very fresh. Other sources may not be any better tube, but if they sit for a few years and get stale, then they do that rip a hole thing you have experienced.

Nothing that special about bottranger, I get some failures with them, usually a stem ripping off. The tubes cost the same as cheaply made bell brand tubes at wallmart. About 12 bucks for the thick type.

 

[boogieBeats]

I noticed that the spec'ed diameter of the tube makes a difference too. Narrow tubes in a large tire tend to pinch flat for me.

For example. If I have a 26 x 2.00 tire and can choose between a tube made for 1.5" - 2.00" or 1.75 - 2.25, I seem to get less flats on the larger of the two.

 

[Ianhill]

The rubber is stretched and becomes thinner when pumped up in larger tyre so a 1.5-2.00 tube will be at its limit with 2.0 and the 1.75-2.25 will have more stretch left in it so it can take more impact without bursting, I've had alit of trouble with 2.40 tyres in the past I was blaming the tyre compound but found out the tubes were 2.25 limit so they were like clingfilm thick inside the tyre when inflated.

 

[MadRhino]

Wether you need traction for the winter or low rolling resistance for the summer, Schwalbe Mad Mike 2.15 mud thread or Maxxis Hookworm 1.95 slick thread, can be found in 16" for 22$ and both are very robust tires. Try to avoid riding small diameter tires low PSI, for they are hitting road hazards much worse than larger ones.

 

[Kenny'sID]

Perhaps you could post a build thread for your setup, with complete details, pics uploaded in the posts, etc., and we could give you suggestions of what to improve and where/how, for reliability.

Quite a few of us use our bikes for cargo hauling in various conditions, and could help you get set up for never having to worry about that sort of thing again.

That would be of great help. Not only am I trying to do without a car, due to handicap, I can't pedal at all, lol, at least not now, hence the hybrid gas/electric to avoid breakdown, but alas...the best laid plans... I'll get a thread started soon on it, any particular area of the board that is best for that? Thanks so much, AW.

 

[Kenny'sID]

Re tubes,, I pretty much will only run bottranger brand thick tubes from a local bike shop.

Why those? Mostly because the bike shop turns its stock, and the tubes are always very fresh. Other sources may not be any better tube, but if they sit for a few years and get stale, then they do that rip a hole thing you have experienced.

Nothing that special about bottranger, I get some failures with them, usually a stem ripping off. The tubes cost the same as cheaply made bell brand tubes at wallmart. About 12 bucks for the thick type.

You know, I'll just bet that is the problem with these tubes going bad. They look rather old, I mean the box art and such, and the box conditions seemed to indicate the same, as well as the fact, splitting is just what they are doing. I'll look into the brand you mention, and thanks a bunch.

 

[Kenny'sID]

I noticed that the spec'ed diameter of the tube makes a difference too. Narrow tubes in a large tire tend to pinch flat for me.

For example. If I have a 26 x 2.00 tire and can choose between a tube made for 1.5" - 2.00" or 1.75 - 2.25, I seem to get less flats on the larger of the two.

Good to know, I'd a never thought it. I mentioned I was suspicious of anything on this trailer...well, the original tubes were something like I've never seen before as far as the valve stem. I researched it and found a few major type valve stems but nothing on these. The only way to fill them was to put a triggered air chuck over the top, no real locking connection and fire away and get it somewhat full. No valve stem at all, just weird. I got rid if them, like from the frying pan to the fire. Thanks for the helpful tips.

 

[Kenny'sID]

The rubber is stretched and becomes thinner when pumped up in larger tyre so a 1.5-2.00 tube will be at its limit with 2.0 and the 1.75-2.25 will have more stretch left in it so it can take more impact without bursting, I've had alit of trouble with 2.40 tyres in the past I was blaming the tyre compound but found out the tubes were 2.25 limit so they were like clingfilm thick inside the tyre when inflated.

I would have tended to ignore a listed limit, but I guess they are pretty serious abut following it...another good tip, thanks. I bought a big bottle of goop, did 2 bikes and the trailer and thought I'd be ready for anything...I wasn't.

Anyone here ever go the tubeless route? Worth the trouble/bad idea?

 

[Kenny'sID]

Wether you need traction for the winter or low rolling resistance for the summer, Schwalbe Mad Mike 2.15 mud thread or Maxxis Hookworm 1.95 slick thread, can be found in 16" for 22$ and both are very robust tires. Try to avoid riding small diameter tires low PSI, for they are hitting road hazards much worse than larger ones.

More good tips, thanks. And I'll look into those brands. Going to go to ebay now and see if I can find somthing decent, and if I have question abou them, I'll come back here. Guess I'l just go with 16 inchers of the same size. they are listed on the tire at 70kg max weight, so I assume that means I can get double the evenly dispersed weight with two tires? That would come to a supposedly about 300lbs, of which I would likely never have that much weight, just saying, the trailer is probably sufficient without buying anything special for it.

I only went with this trailer because of the frame size, and didn't really like the seat mount tongue system but it turned out ok...much better turning abilities/range. I pulled the bin it had for a bed and a Walmart trunk fit perfectly in this particular trailer. I wanted something I could lock and it turned out to be one of the best looking trailers I've seen, so a bit of a cheap $20 trunk, but I had in mind I might sell it and maybe do another build after I did this one and really knew what I wanted so, looks might help there. Still haven 't decided to sell, it or not. I have decided this is going to work for me once I get past the growing pains, when it worked it was nice and smooth, quiet, plenty fast, and so much more. I'll get into more of what I want if there is a next build, in another thread....thanks all.

 

[amberwolf]

That would be of great help. Not only am I trying to do without a car, due to handicap, I can't pedal at all, lol, at least not now, hence the hybrid gas/electric to avoid breakdown, but alas...the best laid plans... I'll get a thread started soon on it, any particular area of the board that is best for that? Thanks so much, AW.

I'd just use the area this thread is in.

Don't forget to post what you do and need from the build as well as what you already get, and a list of specific issues you have and things you've already tried to solve them. (including the trailer).


Also, you can look at my various threads for my Flatbed Kennel Trailers starting with the one in my signature and working your way back to the older ones, see if that gives you any ideas. And the ones for my SB Cruiser trike and CrazyBike2, and the older DayGlo Avenger bike (which was ok for a "normal" bike) and Delta Tripper (which I wouldn't recommend emulating).

For most of my bike/trike threads I'd start at the ends and work your way back, as that will give you the latest configurations first, the stuff that works, and then see what didnt' work and why...and keep in mind they are all long-winded and rambling with lots of OT stuff thrown in.

 

[Kenny'sID]

That would be of great help. Not only am I trying to do without a car, due to handicap, I can't pedal at all, lol, at least not now, hence the hybrid gas/electric to avoid breakdown, but alas...the best laid plans... I'll get a thread started soon on it, any particular area of the board that is best for that? Thanks so much, AW.

I'd just use the area this thread is in.

Don't forget to post what you do and need from the build as well as what you already get, and a list of specific issues you have and things you've already tried to solve them. (including the trailer).


Also, you can look at my various threads for my Flatbed Kennel Trailers starting with the one in my signature and working your way back to the older ones, see if that gives you any ideas. And the ones for my SB Cruiser trike and CrazyBike2, and the older DayGlo Avenger bike (which was ok for a "normal" bike) and Delta Tripper (which I wouldn't recommend emulating).

For most of my bike/trike threads I'd start at the ends and work your way back, as that will give you the latest configurations first, the stuff that works, and then see what didnt' work and why...and keep in mind they are all long-winded and rambling with lots of OT stuff thrown in.

Thanks AW, I'm still thinking here. One thing I have decided after this last incident/all the trouble I had with her first real test was, believe it or not, I'm sold on these as a viable/serious form of transportation.

I like the idea of the flatbed...if for no other reason, it leaves things open for all kinds of options on what to carry.

I just finished repairing mine, at least partially, as I may wan to go a different rout with the gas engine, and it's drive train. But I won't get into all that now, however I do have a couple of questions before I post so I can decide what direction I'm headed with some of this stuff, and thanks for the advice on how to post, it was helpful.

First question, does anyone here use, or have you ever used a 3hp/4 stroke on a trike?
this predator 6 horse just doesn't seem necessary. I need to get the right sprocket on there as it's a bit tough to get it off the line, bit once I get it going, it does little more than idle and I'm ding 15 to 20mph more or less, so thinking a 3 hp might work better. That would leave me more space in the basket, as well as cut down on the weight.

Also, can y'all just give me a rough estimate of how many miles I should get with the 1000W front hub on same bike, @48v 4x12v 18ah sla batteries? See, after only getting about 4 miles from a full charge, I went to charge this thing up after the incident, and it tested at 58v....way higher than it should have. So what I think happened, is it gave out due to bad connections on the way to the store, and when I charged it at the grocery store, it over charged, yet that same bad connection wouldn't allow me to get but about 4 miles on the way home too. I calculated 20 miles more or less with this battery set up, all depending on the weight I carried, was I way off and can only expect 4 or so miles or was I pretty well in the ball park for MPC?

If the latter, I can assume I just need to tighten some connections and battery problem solved. If I'm off on MPC, then your telling me roughly what I should get, would be very helpful in figuring out if I have another problem or just not enough battery capacity.

Thanks for any input on those questions, and for all the help thus far.

 

[Ianhill]

Sounds like the slas are dead if they charged to 58v that's 14.5v per batt if the charger went to float check each packs voltage make sure they are balanced.
SLA are notorious for failing the Internal resistance shoot through the roof and the cells just can not push the amps no more so the capacity is there but it unobtainable and load placed on the battery's drops the voltage fast.
Slas typically have 6cells in a 12v battery so a 48v batt is 24 cells in series with a tendency to fall on their arse under load they really not the best for driving a motor more suited to a lighter load alarm systems etc.
If you want distance of 20 miles the 48v 18ah will do it but in lipo or 18650 then the capacity stated will reach your goal but generally slas have no business above 15amp some better versions may take upto 40amp for a short period but they will suffer voltage sag then recover and so on, Id say lipo is cheap and is the way to get the odometer rolling round.

 

[amberwolf]

Thanks AW, I'm still thinking here. One thing I have decided after this last incident/all the trouble I had with her first real test was, believe it or not, I'm sold on these as a viable/serious form of transportation.

Yes, they are. Except for going to lunch now and then with my friend Bill, my bike and trike are my exclusive transportation, including cargo hauling of up to hundreds of pounds of stuff at a time, sometimes including a couple of St. Bernards. (one on the trike, one in the trailer).

I generaly travel only a few miles at a time, but sometimes go on 20-50 mile round trips for various things.

I like the idea of the flatbed...if for no other reason, it leaves things open for all kinds of options on what to carry.

That's why I built mine that way. The only one not built that way was Mk III, which was specifically built to carry a kennel for Tiny, but it was also still made to pull that off and put a deck on it if I needed to (mostly, I just took the top off the kennel and carried bigger stuff in the bottom half, when needed). Mk IV is fully flatbed, removable deck, planned to eventually have a removable kennel/crate custom made to cover the whole deck that can carry both dogs at the same time. But it is also much wider than typical bike stuff, and won't fit between bollards on bike paths, etc., so it's street-only.

First question, does anyone here use, or have you ever used a 3hp/4 stroke on a trike?

No, I went electric primarily for silence. I have briefly considered a small Honda generator (cuz they're about the most silent/reliable I know of) for a long road trip between cities so I don't have to stop for recharging (carrying solar sufficient for my stuff is impractical and not deployable while riding). Other than that, though, I wouldn't want to carry ICE stuff on my vehicles. Just a personal preference.

Also, can y'all just give me a rough estimate of how many miles I should get with the 1000W front hub on same bike, @48v 4x12v 18ah sla batteries? See, after only getting about 4 miles from a full charge, I went to charge this thing up after the incident, and it tested at 58v....way higher than it should have.

58V sounds normal for a full charge on 4 12v sla's, at least, during the charge itself, from back when I used that size SLA on my CrazyBike2 with powerchair motors. But they'd drop down to around 54-55v or so once off the charger for a while, IIRC.

I know that I would get something like 10(+?) miles with 3 of those in series, with my brushed powerchair motor system, on my heavy CB2, and though I pedalled I doubt I contributed much other than at startups from a stop. I recharged immediately at the destination, to minimize sulfation problems, but they still didn't last very many cycles before range began to grow shorter and shorter, and eventually I added a fourth in series (cuz I couldn't add 3 more in parallel).

I used some really big/heavy powerchair SLA and got a few more miles out of the system, but because of the extra weight it took so much more power to get started, and was so much harder on the batteries, that it used up so much of the extra capacity it didn't add enough to be worth it.


But if your results/ voltage is different than what you got before, then most likely it's just bad SLA, as noted by Ianhill. Showing a voltage higher than they actually are is common for bad lead, especially if it drops right off once a load is applied. Could be even just one bad cell of the 6 in a battery, but you can't test/replace one cell in there, have to replace the whole battery.

SLA generally doesn't give more than maybe half of it's capacity when used at the high rates we use them at. Since we don't know your terrain, conditions, riding style, etc., we can't estimate how much Wh you are probably using per mile.

Depending on that, you could get 10+ miles out of the system, but if you have a lot of hills or stops/starts, it will reduce the range, possibly by a lot.


If you use a wattmeter you can measure this directly, as well as how much current you are pulling from the batteries at any particular moment. This can help you figure out if you're using the batteries within their limitations, and the voltage sag you see under load can also help you see their health, as large amounts of sag means either the batteries are failing (if they didn't do that before) or they are incapable of handling the load placed on them (if they did that from the beginning).

 

[Lurkin]

Tire sizing sizes are explained pretty well on the schwalbe website. have a look through here: https://www.schwalbetires.com/tech_info/size_markings

I don't know what trailer you have, pics would help. I recently purchased a chinese made bike trailer, been nothing be good, cheap times. However, the tires that came with it were 16", cant remember the rest of the sizing. I ran into trouble buying tyres online because of the effect of the width on the inside diameter of the tyre. This is all explained at the link above.

However, I also found the trailers tyres were the same size as most cheap throwaway kids bikes. The local co op bike place had these in abundance..... super cheap. 8)

 

[Kenny'sID]

Sounds like the slas are dead if they charged to 58v that's 14.5v per batt if the charger went to float check each packs voltage make sure they are balanced.
SLA are notorious for failing the Internal resistance shoot through the roof and the cells just can not push the amps no more so the capacity is there but it unobtainable and load placed on the battery's drops the voltage fast.
Slas typically have 6cells in a 12v battery so a 48v batt is 24 cells in series with a tendency to fall on their arse under load they really not the best for driving a motor more suited to a lighter load alarm systems etc.
If you want distance of 20 miles the 48v 18ah will do it but in lipo or 18650 then the capacity stated will reach your goal but generally slas have no business above 15amp some better versions may take upto 40amp for a short period but they will suffer voltage sag then recover and so on, Id say lipo is cheap and is the way to get the odometer rolling round.

Thanks for a very informative post Ian, look like it not as simple as I thought. You've given me some things to look for, and I'll look into testing the batteries for faults, or just tighten things up, and wait till I can have someone on call for help, and just go for another ride and see how it goes. FWIW, the batteries are fairly new, as in this test was the first time they were discharged...otherwise I just used them to test during the build.

 

[Kenny'sID]

Thanks AW, I'm still thinking here. One thing I have decided after this last incident/all the trouble I had with her first real test was, believe it or not, I'm sold on these as a viable/serious form of transportation.

Yes, they are. Except for going to lunch now and then with my friend Bill, my bike and trike are my exclusive transportation, including cargo hauling of up to hundreds of pounds of stuff at a time, sometimes including a couple of St. Bernards. (one on the trike, one in the trailer).

I generaly travel only a few miles at a time, but sometimes go on 20-50 mile round trips for various things.

I like the idea of the flatbed...if for no other reason, it leaves things open for all kinds of options on what to carry.

That's why I built mine that way. The only one not built that way was Mk III, which was specifically built to carry a kennel for Tiny, but it was also still made to pull that off and put a deck on it if I needed to (mostly, I just took the top off the kennel and carried bigger stuff in the bottom half, when needed). Mk IV is fully flatbed, removable deck, planned to eventually have a removable kennel/crate custom made to cover the whole deck that can carry both dogs at the same time. But it is also much wider than typical bike stuff, and won't fit between bollards on bike paths, etc., so it's street-only.

First question, does anyone here use, or have you ever used a 3hp/4 stroke on a trike?

No, I went electric primarily for silence. I have briefly considered a small Honda generator (cuz they're about the most silent/reliable I know of) for a long road trip between cities so I don't have to stop for recharging (carrying solar sufficient for my stuff is impractical and not deployable while riding). Other than that, though, I wouldn't want to carry ICE stuff on my vehicles. Just a personal preference.

Also, can y'all just give me a rough estimate of how many miles I should get with the 1000W front hub on same bike, @48v 4x12v 18ah sla batteries? See, after only getting about 4 miles from a full charge, I went to charge this thing up after the incident, and it tested at 58v....way higher than it should have.

58V sounds normal for a full charge on 4 12v sla's, at least, during the charge itself, from back when I used that size SLA on my CrazyBike2 with powerchair motors. But they'd drop down to around 54-55v or so once off the charger for a while, IIRC.

I know that I would get something like 10(+?) miles with 3 of those in series, with my brushed powerchair motor system, on my heavy CB2, and though I pedalled I doubt I contributed much other than at startups from a stop. I recharged immediately at the destination, to minimize sulfation problems, but they still didn't last very many cycles before range began to grow shorter and shorter, and eventually I added a fourth in series (cuz I couldn't add 3 more in parallel).

I used some really big/heavy powerchair SLA and got a few more miles out of the system, but because of the extra weight it took so much more power to get started, and was so much harder on the batteries, that it used up so much of the extra capacity it didn't add enough to be worth it.


But if your results/ voltage is different than what you got before, then most likely it's just bad SLA, as noted by Ianhill. Showing a voltage higher than they actually are is common for bad lead, especially if it drops right off once a load is applied. Could be even just one bad cell of the 6 in a battery, but you can't test/replace one cell in there, have to replace the whole battery.

SLA generally doesn't give more than maybe half of it's capacity when used at the high rates we use them at. Since we don't know your terrain, conditions, riding style, etc., we can't estimate how much Wh you are probably using per mile.

Depending on that, you could get 10+ miles out of the system, but if you have a lot of hills or stops/starts, it will reduce the range, possibly by a lot.


If you use a wattmeter you can measure this directly, as well as how much current you are pulling from the batteries at any particular moment. This can help you figure out if you're using the batteries within their limitations, and the voltage sag you see under load can also help you see their health, as large amounts of sag means either the batteries are failing (if they didn't do that before) or they are incapable of handling the load placed on them (if they did that from the beginning).

Thanks, AW, more good tips.

The reason I need the gas is mainly for emergency, and it doesn't even have to do that great a job, just get me home since the handicap won't allow me to pedal. I imagine the gas engine would come in handy at other times, but that's it's major purpose. I too like the quiet...a main reason I mentioned the fact I was sold. When this was running right on electrical power, it was quiet, smooth, plenty of power...just great. All I could think of to add were maybe some shocks, but even without that, it's fine.

I'm slowly gathering 18650's for a battery build, and I think I'm at about 70 or 80 count, all new and tested seemingly good batteries. I'll be here to get help with it and once complete, I have a feeling I'll be able to appreciate these bikes a lot more.

I considered the generator as well, even ordered one but the guy sent the wrong one, I returned it and decided not to order/get ahead of myself till I decided what I really need.. I'm also considering a solar trailer of some sort...pretty much built from solar panels, but all that will have to wait till I get the basics on the road, then the real fun begins, of making a better bike.

And yeah, can't beat a flat bed, especially for those "Tiny" loads.

 

[Kenny'sID]

Tire sizing sizes are explained pretty well on the schwalbe website. have a look through here: https://www.schwalbetires.com/tech_info/size_markings

I don't know what trailer you have, pics would help. I recently purchased a chinese made bike trailer, been nothing be good, cheap times. However, the tires that came with it were 16", cant remember the rest of the sizing. I ran into trouble buying tyres online because of the effect of the width on the inside diameter of the tyre. This is all explained at the link above.

However, I also found the trailers tyres were the same size as most cheap throwaway kids bikes. The local co op bike place had these in abundance..... super cheap. 8)

Lurkin, I'll keep that site in mind for tires, and will get pics up eventually. I think this is a China trailer too, got it off ebay, and cheap is certainly the rule with it. It was one of the few cargo trailers that have the seat mount hitch, the only thing I didn't like at ordering, however, turns out, the turning capabilities are much better than than a wheel/axle mount.

For now I just went with Walmart, Bell tube and tire...that way at least I know the tubes haven't been sitting in a warehouse for who knows how long and rotting as I suspect was the problem with the ebay cheap tubes. I do think the Bell tire was a cheap kids bike tire, as mentioned. I don't think I want to sink a lot into this trailer, as I'll likely end up with a better basic one later, and then modify it, if needed.

 

[amberwolf]

If you're willing to invest in a cheap wirefeed welder from HarborFreight, Craigslist, etc., you can build yourself a much better trailer.

So far the Mk IV has been the best performer, most stable, best ride, etc. Would still work even if narrower (for bike path bollards, etc). If you prefer the seatpost mount, you could use that in place of the automotive hitch that I use. But the larger 26" wheels ride better and smoother, and the lowered below-axle deck ends up still about the same height, maybe a little lower, than a 16" or 20" wheeled kid's trailer. Can be built for as low a deck as you like. Could be built from any steel tubing (conduit, etc); could even be built from old bikes. Could be bolted together if you don't want to weld, but the welded version can be tough as heck.

 

[Kenny'sID]

If you're willing to invest in a cheap wirefeed welder from HarborFreight, Craigslist, etc., you can build yourself a much better trailer.

So far the Mk IV has been the best performer, most stable, best ride, etc. Would still work even if narrower (for bike path bollards, etc). If you prefer the seatpost mount, you could use that in place of the automotive hitch that I use. But the larger 26" wheels ride better and smoother, and the lowered below-axle deck ends up still about the same height, maybe a little lower, than a 16" or 20" wheeled kid's trailer. Can be built for as low a deck as you like. Could be built from any steel tubing (conduit, etc); could even be built from old bikes. Could be bolted together if you don't want to weld, but the welded version can be tough as heck.

I have a little miller wire feed, and it's true it's just for small stuff, but I be darned if I could ever get the hang of using the thing. Of course I haven't tried it in years, or since youtube has been around so maybe I can find a tutorial there to help me out. S4eems with youtube, one can do just about anything.

Good to know they can be bolted if it comes to that, I did consider one out of conduit, seems cheap enough to make, and the portability of bolt together could come inn handy for me. I have considered it, and eventually may well go that route.

I have to get another tire now for the trailer because the one I ordered was much bigger than the original, but that's fine, it's much beefier too and these better tires should help me get by with what I have a little better, at least for awhile.

I have a 2 wheeler sidewinder/Schwinn with a cheap ebay 2 stroke and 1000w front hub that I think I'm going to concentrate on now. It's all ready (electric drive tested fine)but I haven't been able to get the 2 stoke to fire at all. It has spark, but I hear these are notorious for bad coils so it may be too weak a spark. I'll get another thread up on that one and once I get it done, I can concentrate on the 3 wheeler as I need at least one on the road. Plus I want to see just what the 2 stroke 60cc's are capable of. Thought about putting one on the 3 wheeler, and I don't really care if it's slow on top end, if it'll just get me off the line without pedaling for emergency situations if the electric drive goes out, it'll be fine.

 

[Kenny'sID]

Sounds like the slas are dead if they charged to 58v that's 14.5v per batt if the charger went to float check each packs voltage make sure they are balanced.
SLA are notorious for failing the Internal resistance shoot through the roof and the cells just can not push the amps no more so the capacity is there but it unobtainable and load placed on the battery's drops the voltage fast.
Slas typically have 6cells in a 12v battery so a 48v batt is 24 cells in series with a tendency to fall on their arse under load they really not the best for driving a motor more suited to a lighter load alarm systems etc.
If you want distance of 20 miles the 48v 18ah will do it but in lipo or 18650 then the capacity stated will reach your goal but generally slas have no business above 15amp some better versions may take upto 40amp for a short period but they will suffer voltage sag then recover and so on, Id say lipo is cheap and is the way to get the odometer rolling round.

Lanhill, 3 of the batteries showed around 13.5 volts each, and one @ a little over 11v. It's taken several hours but I finally got it up to 12.5 and will just have to see if it'll charge back up the same as the others. I just wanted to run that past you since you seem to be the man when it comes to this area, and see if anything comes to mind.

Also, my intention is to build an 18650 pack as soon as I have enough batteries, and I was hoping you could give me a rough idea (I'm terrible at the math on this stuff) of how many 18650's I need to get the 18ah's I need? I have 70 or so thus far, all new, and most at a nominal 2200mah each. 48 of the same type and within about 50mah of each other but most of the remaining are close to that or better.

 

[amberwolf]

and one @ a little over 11v.

That one is probably toast. It probably doesnt' have the same capacity as the others, or a bad cell in it, so even if it ends up charging to "full" it will run down faster than the others, cutting off the system early, and the whole series string will not work as expected because of it's internal problems.

Also, my intention is to build an 18650 pack as soon as I have enough batteries, and I was hoping you could give me a rough idea (I'm terrible at the math on this stuff) of how many 18650's I need to get the 18ah's I need?

If you need 18Ah, you divide that by the capacity of the cells you are using (2.2Ah), and round up to the next whole number. That's how many parallel cells you need.

THen divide the pack voltage you need (at full charge) (56-60v?) by the full charge voltage of the cells you are using (4.2v), and round up to the next whole number. That's how many series cells you need.

Multiply the two number and that's how many total cells you need.


Also keep in mind that you need to know how much current (amps) your system pulls at peak, and how much at normal cruising load, because the pack has to be able to deliver that without straining it.

Then you need to know the C-rate of the cells you have, so you know how many total parallel packs of the above size that you need to support the current draw of the system. If you don't know the C-rate, then you would need to build the pack of assorted cells, and then test it on the system and see what the voltage sag is under load. If it is too much sag (more than a couple of volts or so, to really keep the cells happy) then you probably need more parallel pack(s).


There are a lot of threads on how to build packs out of 18650s, and I highly recommend reading as many of them as you can to get ideas on doing it, and knowledge of exactly how to determine how big a pack you need, based on others' experiences.

It isn't really simple to build a pack of used cells, if you want it to work consistently throughout the pack for a long time (unless you just build it hugely larger capacity than you need it to be, many times more, so there is very little load on it, as that is what most of the used cells people find seem to be meant for).