Show me your 700c! (Or, Project "electro weight weenie")

Ok, I'm at a cross-roads here, I just rode up the monster hill in Oregon City earlier today (even in the 85 - 90 DEG weather!) on my "new to me" Bianchi road bike and I will have to do it again to confirm that the GPS was re-set and not just showing an old average speed, but when I got home, I had virtually the same average speed as my E-Bike!

If this is confirmed, I will be getting myself the lightest most efficiant motor I can get, and see about hooking it up to my Bianchi with the most energy dense LiPo I can afford and see if I can keep the motor & battery down to 10 - 15 lbs.

Anyone done this? Or am I dreaming? :lol:

On the flip side, I will see how much voltage I can push to get some more pep out of my current hub motor, if not, I will go all out on a big DD motor, maybe a XLight 5304 and have one bike for when I'm feeling energetic and one for when I'm not.

SO .... if anyone has built a super light efficient road bike, please post your info here thanks! 8)

This is exactly what we were going with, for my buddys bike. However, we copped out a little (alot) with the batteries and got lead, just because he couldn't afford the lithium and I didnt have the time to build it for him. We just got started but I think there is a huge space for ebikes with very small efficient batteries!

http://endless-sphere.com/forums/viewtopic.php?f=6&t=19772

You're my hero! 8)

I've come the conclusion that I need to stop trying to make one bike be a jack of all trades and just make 2 E-Bikes: One fast as I dare, the other light and efficient as possible.

I hear ya on the batteries, and it will probably be a year coming before I have the chance to realize my dream of an electric road bike, I have to ask, how well do the wheels deal with the weight of the SLA's?

My biggest concern for a build of this type is the strain of batteries and motor on such narrow wheels, not to mention a rigid frame taking all the punishment of the bumps to top it off.

I'm also wanting to keep a budget low, but I have seen what lead acids do to a 26" wheel, but maybe that isn't the same.

What would REALLY be kewl is a TT style rear hub motor wheel with 3 spokes! Out of my price range, but it would still be sweet!

My bike is a 700c setup. You can read the thread in my sig if you care to.

TJG

Yes indeed, multiple bikes is the real solution to all problems. Now that I have some light lipo, I find myself wondering about a amped rear hub, and a controller that likes 18v. It wouldn't be much assist, but a sub 5 pound 10 ah battery, tiny controller, and 8 pound motor sounds good. No heavier than a mtb or beach cruiser, but with assist up hills. HMMMM. Range would be short, but if you only used the motor 30% of the ride big deal. While it's over 95F though, I'll stick to a heavy dd motor that goes forever with a big battery.

You might be interested in Kepler's friction drive.
Here is the link.

kepler said:

So my main criteria were for the new system to have as little impact on the standard bike as possible. It would be used primarily as a hill assist with the bike ridden as a normal bike most of the time. Target checklist is as follows.

=> 2 Kg in weight including battery
=> No drag at all on the bike when throttled off
=> Very quick release and re fit (30 second target)
=> 6S LiPo configuration to utilize cheap low Voltage speed controllers
=> 1000 Watt max output
=> 40 kph top speed
=> Very compact configuration

Click to expand...

- Adrian

adrian_sm said:

You might be interested in Kepler's friction drive.
Here is the link.

kepler said:

So my main criteria were for the new system to have as little impact on the standard bike as possible. It would be used primarily as a hill assist with the bike ridden as a normal bike most of the time. Target checklist is as follows.

=> 2 Kg in weight including battery
=> No drag at all on the bike when throttled off
=> Very quick release and re fit (30 second target)
=> 6S LiPo configuration to utilize cheap low Voltage speed controllers
=> 1000 Watt max output
=> 40 kph top speed
=> Very compact configuration

Click to expand...

- Adrian

Click to expand...

OMG!! if that E-Bike was a woman, I would be asking her to marry me!

That friction drive is incredible!!! I never would have given a friction drive a second thought until I learned about this one, WOWOWWOWOWOWOWWOW!!!

Thanks a TON for the link!!

Here's mine on 700c tubulars. With this rack from a Bell child seat, the bike is around 45 lbs with the 15AH PingV1.

Fantastic Rayy! That's really light! How much of the 45lbs is just the bike?

How many watts does that put out, and will it climb hills with no pedaling? I really wouldn't care if it went really slow up-hill so long as it would do it on it's own.

Is there a build thread for your bike?

Thanks LI-ghtcycle. The bike is around 23lbs. The rack itself is around 4lbs but it was what I had lying around, so I used it. I wanted the rack for a larger battery pack for some long distance riding. Previously, I had the battery in a small rack mounted to the water bottle bosses and the bike weighed in around 42lbs.

Sorry, no build thread. I built this over 2 years ago, long before I joined this forum. The motor is an old Kollmorgen/Currie 400watt driving thru a Spectro P5 internal gear hub. (There is a 600Watt MAC motor that would work too.) I geared it so 5th will get me about 42-43kph without pedaling and around 46-47kph with me assisting. Thus 1st gear will get my 175lbs up a 7% hill at 15kph consuming around 350watts. When I had 5th geared for 32kph, I could get up some really steep hills but I prefer the faster speed. So depending on how much you weigh and how steep of a hill you want to climb, you could always adjust the driven gear to suite your needs. I'm curious though, why do you want to climb without pedaling?

Interesting thread.

Especially after the discussion about racing when some were questioning whether a good bike could be built under 70 lbs. I think we have the answer.

I don't understand why so many people are hung up on the need for dual suspension. Once you go down that route you need to beef everything up to stop frame flexing at speed. You end up re-inventing the motorcycle. For road bicycles its much better to keep it simple and light.

Nick

I don't want to climb with out pedaling, but if I find myself in on a bad day and my chronic fatigue wipes me out, I would like to know that the bike will still get me home reasonably well.

I have been having a really excellent week and have been just riding the Bianchi. I'm really leaning towards the Kepler friction motor set-up! 8)

Tiberius said:

Interesting thread.

Especially after the discussion about racing when some were questioning whether a good bike could be built under 70 lbs. I think we have the answer.

I don't understand why so many people are hung up on the need for dual suspension. Once you go down that route you need to beef everything up to stop frame flexing at speed. You end up re-inventing the motorcycle. For road bicycles its much better to keep it simple and light.

Nick

Click to expand...

Agreed!

I have my current E-Bike for going on gravel, long distances and riding at night (lights) and I will probably trade with my father for his 9c motor and run it at 72V so it will make enough power to where it's performance off-sets it's weight.

Ok LI-ghtcycle, I understand. From your questions, it sounded like you wanted a bike to carry you up all hills. To get home, make sure you have excess capacity from your battery. Another suggestion is a granny gear. I only had to use mine once (when I found out I had a couple of bad cells) but I certainly needed it with a couple of big hill on the way back.

Come now Tiberius, you know it's impossible to duck 70 lbs. Must have a giant flexy full suspension to make an ebike for a kart track race. Why would you want to use a light rigid frame designed around smooth surface racing for a race on a smooth surface?
(for the confused Canadians, that was called sarcasim.)

I'm loving the machines I'm seeing in this thread! I gotta build a light road racer for myself

Tiberius said:

Interesting thread.

Especially after the discussion about racing when some were questioning whether a good bike could be built under 70 lbs. I think we have the answer.

I don't understand why so many people are hung up on the need for dual suspension. Once you go down that route you need to beef everything up to stop frame flexing at speed. You end up re-inventing the motorcycle. For road bicycles its much better to keep it simple and light.

Nick

Click to expand...

Oh boy, more Canadian bashing I had no idea you hated it that much up here! Don't expect me to ride your bike for your lazy ass ever again! (Actually let's hope that's the case as next time maybe you'll remember the brackets etc. Silly Americans.... )

Some guy at the bowling alley the other day let me ride his super light $3000 road bike. It was soooo nice, I felt like I could just blaze down the streets, and he was keeping pace with me pretty darn good (50km/hr) on the way home. Add a little motor for uphills and your set.

PS: It's sarcasm.... :lol:

Sad that you have to qualify to denote the sarcasm there. But I guess that's the end result of our greatest export to the USA being comedians (Hollywood would be all Action and Chick flick if it wasn't for us). The ones that are left are more likely to be humourless, as so many of the funny ones head south for the fat paycheques.

Back on topic - thanks for the link to Kepler's project that I had not noticed before. While my 9c commuter is nice as a reliable hauler for pulling the kid in trailer - I really feel the weight. I have an older Cannondale road bike kicking around that I have not used in a while and that friction drive sounds like it would make a great match - I particularly love the idea of plugging in as many 6s lipo packs as required by the range for a given task.

My 700c build !

Bike: Schwinn full race (KMart) 8).
Kit: Elation 200w
Drop bar converted to flat courtesy of the local tip.

This thing is light and FAST but I really can't afford to have punctures every 2 weeks on my way to work!

Beautiful!!

zx6rj1 said:

My 700c build !

Bike: Schwinn full race (KMart) 8).
Kit: Elation 200w
Drop bar converted to flat courtesy of the local tip.

This thing is light and FAST but I really can't afford to have punctures every 2 weeks on my way to work!

Click to expand...

Beautiful!

Have you tried some of the anti-puncture strips? I know that there are some tires made by Schwalbe that claim to be fairly puncture resistant, but idk, I just hear good things about how long their marathon tires last.

My 2807 9C/ 48V 15 ah Ping is on a 700c Schwinn Passage base. Very fast (~30 mph with pedal), excellent climbing and range. Total weight is under 60 lbs. I have put about 1000 miles on it over the last 2 months commuting. Major drawback - back problems. Going 30 on rock-hard skinny tires is killing me. Got a Thudbuster seatpost on order, and a Kona Worldbike waiting in the wings (with 2.35" Schwalbe Big Apples) if the Schwinn can't be made to work.

Oh, about punctures. I tried strips, and tires "guaranteed" not to get flats. I had about a dozen pinch flats from trying to get the darn special rock-hard too-small tire on. After getting some lively 25 mm Panaracers the problems with flats were over. Face it, flats are going to happen - but my experience with trying to prevent them with "special" tires/tubes/strips didn't work out too well, it was much better getting a tire I could actually change easily.

Nooooo! I never would have made it back to the shop with out you! You're in damn good shape! This guy pedaled my half assembled pig of a downhill bike up a mile long monster of a hill like an animal. My bike is awful to ride with no assist,and this trooper didn't fuss a bit! Riding his 530x powered bike up the hill was a lifesaver for my out of shape ass. Lol

I loved every bit of my time in Canada, and you guys were fantastic! I just gotta rib a couple of the more sensitive Canucks on the board once in a while, can't have them running out of things to stew a-boot

Demosthenes said:

Oh boy, more Canadian bashing I had no idea you hated it that much up here! Don't expect me to ride your bike for your lazy ass ever again! (Actually let's hope that's the case as next time maybe you'll remember the brackets etc. Silly Americans.... )

Some guy at the bowling alley the other day let me ride his super light $3000 road bike. It was soooo nice, I felt like I could just blaze down the streets, and he was keeping pace with me pretty darn good (50km/hr) on the way home. Add a little motor for uphills and your set.

PS: It's sarcasm.... :lol:

Click to expand...

Yeah, I would love to see a competitive road racer using an E-bike at the death race, wouldn't it be great if the main ingredient of the gasser's demise was simple pedaling?! :lol: :lol:

I'm really spoiled now living in Oregon City where the roads are really pretty good, when I get back home to Montana, I don't think I will be using a 700c too much except down-town Missoula.

I'm gonna have to grab one of these Keplers as soon as they are available and try it out on my Bianchi.

The best part is that if anything goes screwy you can just goto the local hobby shop and have them check out the motor/controller etc. if your like me and unable to properly diagnose a problem that is in the electronics.

I built a 700c commuter and tried many things to make the normal street ride tolleratabl. Big spring gel seat, suspension post and stem all worked great to soften road imperfections. Plus large armadillo tires to eliminate flats and further soften the harsh reality of rolling down streets at 30mph. Even with all the crap... the bike came in at 63lbs with 15Ah 48v battery, bags, lock, tools etc...


The thing is, that while it went fast easily ... it simply does not handle well when the surface is rough. Those rough areas are where you need handling the most! I discovered that large/wide tires designed to roll well at lower pressures worked vastly better than what I found to fit 700c wheels. A direct comparison I first had was riding a cruiser type ebike with fat tires on a same route and speeds as my 700c. The cruiser stopped so much easier and maneuvered through conditions without jitter or surface skip despite considerably more weight. I could actually ride it a few mph more without being on the edge. I was sort of fine with my 700c until riding that bike.

I certainly like that super light friction drive and I bet it's super cool to ride on/in the right conditions! Very nice 700c!

Building a bike "fit" to its primary use makes for a higher level of long term satisfaction. Some build for style, price, efficiency, weight, distance, utility, etc... Here we show 700c ... why do we pick a 700c? Who started with 700c and now only rides one if unpowered? How many go over 30mph? Again, "fit" for use or purpose ... a why...?