I do not like the walk of shame :-(

[Xanda2260]

Was testing my new battery box last night when it disintergrated, dumping my lipo on to the floor!
Had to do the walk of shame for 2 miles home...:-(
Packs seem ok, we'll see what happens when they charge...

For full details click link in sig.

 

[Haste]

the worst is the petrol bikes, that decide to run great until your 10 miles away from home lol.

 

[neptronix]

Gave up making a battery enclosure long ago.. triangle bags, rear rack, front forked clamped racks ftw..

 

[Xanda2260]

Gave up making a battery enclosure long ago.. triangle bags, rear rack, front forked clamped racks ftw..

Unfortunately it's a trike, a bag that hangs behind the seat would be cool, but the straps will rip out eventually...
Meh

 

[Kingfish]

I know that walk after suffering from several cheap balloon tubes and rim flats – walking the bike several miles home, until I put how to triple-armor the holey Kris Holm rims with three layers: plastic layer that comes with the rim, Stop-Flats over that, and Velox as the final layer. Gawds I hated that walk. :x

~KF

 

[Xanda2260]

Thats an impressive setup. You must really hate flats!
Havent had a flat in 3 yrs thanks to schwalbe marathon plus tyres ( and 85psi). Just lousy homemade battboxes

Here's attempt number 3. We'll see if it holds up any better...

 

[John in CR]

That's why I always ride up a slight grade when testing new stuff. Then I can get home coasting and avoid the walk of shame. Once you find the limits, then no more failures if you build well, and that's my priority...durability.

John

 

[Sacman]

I know that walk after suffering from several cheap balloon tubes and rim flats – walking the bike several miles home, until I put how to triple-armor the holey Kris Holm rims with three layers: plastic layer that comes with the rim, Stop-Flats over that, and Velox as the final layer. Gawds I hated that walk. :x

~KF

Really ... multiple layers of rim tape and tire liners are all you use on your long excursions?
Somehow I thought for sure you'd be running a tire sealant like Stan's or Slime to ensure you would never get stuck from a tire flat.

 

[Sacman]

Was testing my new battery box last night when it disintergrated, dumping my lipo on to the floor!
Had to do the walk of shame for 2 miles home...:-(
Packs seem ok, we'll see what happens when they charge...

For full details click link in sig.

Look on the bright side ...(yes there's always one).
At least it didn't start to rain and you didn't end up soggy when you finally got home like i did.

 

[dogman dan]

MDF for the fail. you need to build from good hardwoods, and stiff but thin materials like alumimum plate.

Rely on good materials, not funky arrangements of corner braces.

 

[Kingfish]

I know that walk after suffering from several cheap balloon tubes and rim flats – walking the bike several miles home, until I put how to triple-armor the holey Kris Holm rims with three layers: plastic layer that comes with the rim, Stop-Flats over that, and Velox as the final layer. Gawds I hated that walk. :x

~KF

Really ... multiple layers of rim tape and tire liners are all you use on your long excursions?
Somehow I thought for sure you'd be running a tire sealant like Stan's or Slime to ensure you would never get stuck from a tire flat.

Sacman

The tire experience was difficult to swallow leading up to the road trip. At least twice I had rim flats due exclusively to the Kris Holm competition rims, the ones that have weight-saving holes cut out. IMO – it was a complete waste of money to purchase those rims because the cutouts have a sharp edge. Rim tape comes with the rims, but it is thin stretchy film. I was running the Maxxis tubes which are also thin, and the rim cut right through it on the inside. And as I said, this happened to me twice, so here’s the low-down on the protection beginning with the center of the wheel (excluding spokes):

• Rim|Black Plastic Rim Tape|Stop Flats II|Wide Velox to hold it all together|Thick-walled DH tube (Kenda or Q-Tubes, with Slime or latex inside)|Panaracer FlatAway Tire Liner or Stop Flats II|Hookworm 2-Ply.

Except for that flat caused by the wicked 1/4 –inch lag bolt that penetrated the tire on the leg between Pioneer/Jackson and Fresno, I did not suffer from anymore flats. Nothing could have stopped that lag bolt, except maybe railroad wheels instead of tires. No amount of sealant would have stopped it; sealant doesn't stop inch-long rim-sliced flats either.

If this sounds like a pain in the rump to setup (and fix in the field), it is and was. Not interested in a repeat thus I am moving to thicker tougher belted DOT-rated tires.
Best, KF

 

[liveforphysics]

That's why I always ride up a slight grade when testing new stuff. Then I can get home coasting and avoid the walk of shame. Once you find the limits, then no more failures if you build well, and that's my priority...durability.

John

LOL, that's how I test new setups too. Just keep riding uphill while sorting the bugs out of a new setup, then you can always coast back home.

 

[Hillhater]

Was testing my new battery box last night when it disintergrated, dumping my lipo on to the floor!
Had to do the walk of shame for 2 miles home...:-(

Wot ? ...no pedals ???
I would not let an electrical failure force me to walk, and flats can be tricky especially if they are a blow out !!
If you have ever had to walk/carry an Ebike with a blown tube,.. all the way across the city,..and up the longest hill..... you will never get caught without a spare tube !! :x

 

[amberwolf]

I almost had to do a 15-mile walk of shame home from work a week and a half ago, when the clutch in the Fusin geared hub on DayGlo Avenger cracked open and wouldn't transfer power from motor to wheel. I found that after a mile I simply wasn't gonna be able to pedal it home, mostly because I use an "airless" solid tube on the rear wheel that is like 30PSI or less equivalent, adding so much rolling resistance drag on the heavy back end plus me as a rider that I coudln't put out enough power myself to keep going on the slight uphill (whcih is several miles long); my knees just hurt way too much--that's why I have the motors, really.

Fortunately I was able to fix the clutch with a radiator hose clamp temporarily, though ti was tearing up the inside of the hub casing side cover, coating the rest of the motor with aluminum dust and shavings. But about half a mile from home I was forced to switch back to pedals only and then almost walking it, when the motor overheated from running ti too slow with the load on it, trying not to break the clutch repair.


Then a week after that, this past Friday morning, I really did have to do a three-mile-long hour-plus walk fo shame with CrazyBike2 because the rear tire blew out, tube and all, unpatchable (tube torn up and tangled in chain and freewheel, had to cut it out to even roll the bike). That super-sucked, and left my arms and hands going randomly numb for days (actually it is still happening sometimes), and my whole body still aches from pushing the bike that far.

Worst part was knowing that I could have prevented the whole thing by simply changing out the tire that I KNEW was going to pop any time now, but not having had the energy or time due to work and stress.

I had a spare tube with me but I simply couldn't handle the tools and whatnot to get the bike apart enough (and back together again afterward) to install it. Plus the tire was so torn up in two differnet places that I doubt the tube would've lasted 5 minutes even walkign teh bike.

Then after fixing that and some other things on the bike, on the first test ride the rear tube sprang a medium-slowish leak a couple miles into the three-mile test ride around the neighborhood, and I ended up walking home the last maybe 3/4 of a mile or less, because I didn't have a working pump with me. Nowhere near as bad as the 3-mile walk, beause the tire had enough air in it to roll well, as long as my weight wasn't on it. Way less sucky than before, and shorter.


If I had moped tires/tubes/rims on the two bikes, I wouldn't likely have had either problem (because it'd've prevented the flat on CB2 both times, probably, and would've been high enough pressure or at least could be aired up to higher pressures on DGA).

 

[John in CR]

That's why I always ride up a slight grade when testing new stuff. Then I can get home coasting and avoid the walk of shame. Once you find the limits, then no more failures if you build well, and that's my priority...durability.

John

LOL, that's how I test new setups too. Just keep riding uphill while sorting the bugs out of a new setup, then you can always coast back home.

What can I say?...Great minds think alike. :lol: I just wish I'd gone a different route in school, so now I'm playing catchup and having to leave the advanced stuff to you experts.

 

[MadRhino]

He he, I do the same by luck. Living at the bottom of the mountain makes it easy, if something fails I can ride back almost as fast.

 

[Xanda2260]

MDF for the fail. you need to build from good hardwoods, and stiff but thin materials like alumimum plate.

Rely on good materials, not funky arrangements of corner braces.

The one that failed was aluminium plate...
This is only gonna be temp anyway, I'm gonna alter the frame so the box is supported from beneath, that way loads from bumps are compressional, not tensional.

 

[dogman dan]

Hmm, well if designed as poorly as the mdf one in the pic, that's no suprise. Batteries are quite heavy, even lightweight lipo. I see plenty of, if one screw fails the whole thing will fail in your mdf design.

 

[Xanda2260]

Really? It's that bad? The problem with the all one was I used a 2 part putty to hold the pieces together. It was too brittle and cracked under the shock of repeated bumps. Figured this should work, each side has 6 screws holding it on, plus strapping to resist the type of failure on the last box. It's just hideous.

I'd appreciate any design suggestions you may have dogman, or anyone else for that matter.
Currently idea is to abandon the top mount and make up a farfle style box.

 

[dogman dan]

The thing about mdf is that screws will rip out quite easily when subject to shocks and vibration. So use of a better material, like poplar lumber rather than pine, aspen or most plywoods would help a lot. If you do need to rely on some metal straps or braces, try to use something wider. Something that will allow the use of many screws instead of just a few.

My saddlebag style boxes are made from poplar and 1/8 aluminum plate. The inner plate is solidly bolted to the frame, then the alu sides are held to the wood with a screw in a pre drilled hole every few inches. No single screw is loaded much, and none with a pull, only shear loads.

This bike has been crashed several times, and a similar box on my dirt bike has taken some really good crashes.



Looking at your design, perhaps some thicker metal could be welded to the frame, which would extend to the bottom of the box. Then a metal cross piece can connect, perhaps with bolts, to the metal supports completing a bottom support solidly attached to the frame.

Basicly, I'm saying support the box from the bottom with a solid frame attachment. Right now, you basicly have wood hanging from a few bolts. If the MDF cracks near those bolts, the whole box will drop right off the bike as you have it in the pic I see.

It could be just some thicker strapping, running around the entire box, but also connecting to the bolts the box hangs from.

 

[Xanda2260]

Cool, cheers Dogman, almost all the screws on this setup should see shear loads, but I take your point about mdf and screws pulling out. I also think I went too thin on the mdf, I can see bulges in places where the screws enter, and yes, I did drill pilot holes.

I've decided to extend the lower boom to form a platform for the box to sit. It seems the seat back mount puts very heavy tension loads on things, I'd prefer compressive forces, especially when they are the huge shocks from potholes at 40mph! It's telling that a tupperware container ducktaped to the rear rack survived 20mph of testing, but the aluminium box failed in 2. Gonna see if I can get some steel plate (I can weld that), otherwise I might try to make a new Ali box, but bolted together, rather than epoxied. I'll also try to find a source of decent hardwood, give that a try too.

Keep the tips coming guys, it seems I need them!

 

[dogman dan]

Seems to me that even the mdf will work with more support from the bottom, that attaches directly to the frame, rather than hanging the box.

Looking at the sides, the wing nut and brackets are not that bad, but I'd be inclined to put 4 of them on the box instead of two.

 

[Xanda2260]

That should say '20 miles of testing', not 20mph... Bloody autocorrect!

 

[Xanda2260]

Seems to me that even the mdf will work with more support from the bottom, that attaches directly to the frame, rather than hanging the box.

Looking at the sides, the wing nut and brackets are not that bad, but I'd be inclined to put 4 of them on the box instead of two.

The wing nuts just hold the side on so I can get it off to get at wiring. The batteries themselves are mounted at the other end, and held in place by a strip of wood. Defo abandoning top mount, and if I do stick with MDF I'll need to go thicker.
I appreciate your input, last thing I want is £300 of lipo hitting the deck again!

 

[Xanda2260]

Wot ? ...no pedals ???
I would not let an electrical failure force me to walk, and flats can be tricky especially if they are a blow out !!
If you have ever had to walk/carry an Ebike with a blown tube,.. all the way across the city,..and up the longest hill..... you will never get caught without a spare tube !! :x

Pedals were out as the chain fouled on the remains of the box. It was gonna need an idler pulley to sort it, even if the box worked. I also left every tool at home, so removing the box was impossible.
Hills would be great, but I live in East Anglia. The biggest hill within 10miles is less than 100 vertices feet, and it takes nearly a mile to do that!