recumpence
1 GW
For those who are reading this thread for the first time, this bike has now (9-22-12) been sold. It is being built up with two 3220s. The following text is about the original plan for me to build this bike with one 3220 for myself. However, the bike is now sold and I am building it for a high-end client. If you would like to begin with the new layout twin 3220 build, that part begins on page three.
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Hey Guys!
This started way back when I built the PK Ripper BMX bike. That bike was far more fun than any other bike I have built. However, it was too short (wheelbase) and had no suspension. I have had many requests for another 20 inch build and I began moving in that direction when I built the Cannondale Hooligan (Crimson) late last year. That bike looked to be a perfect candidate for an electric conversion. However, the lack of rear suspension was an issue as was the seat to rear wheel relationship. That bike is VERY wheelie prone. That is fine for pedalling, but not for high powered E-bike work. On top of all that, I had this Diamondback X6 frame sitting around (built by Intense Racing back in 99). This frame was bought for its perfect frame setup. There is room in the triangle for lipo and a high, round downtube for drive unit mounting. It also has a great swingarm for left side chain clearance.
That brings us to last week. My work has slowed down and I have been looking at various projects. However, money is tight. So, I did not want to buy anything new. So, I began doing some calculating and figured out that my X6 frame would work if I used a longer shock (I had one lying around) and flipped the shock linkage upside-down. This would drop the swingarm to the correct level for a 20 inch wheel (to have the proper crank height). So, I took my beat up X6 frame to the powder-coater for some gloss black and promptly disassembled my Crimson red Hooligan. Then I built up this bike with those parts and we have what you see here.
When I reconfigured the frame for 20 inch wheel use a couple cool things happened. First, the rear end is plenty long. This is great for a forward CG. It also rotated the frame forward, thus steepening the head tube angle. This sets up the geometry for proper road riding. I think the head tube angle looks a bit too steep. But, the bike handles phenominally like this. The wheelbase is also longer than my Hooligan (way longer than a BMX bike). This makes the bike far more stable while retaining sharp steering with the steep head tube angle. The forks are White Brother's Groove 180s shortened to 4 inch travel for me by White. The brakes are Hope 2 piston units. I may to to a 4 piston up front. We shall see. The wheels are Industry Nine custom items using my 47mm wide rear rim. I have another set of wheels like this that use standard spokes and hubes. I may use those and save these to put back on the red Hooligan as a peadl only bike. I have to see how things go with these wheels.
You can see the HUGE amount of room under the down tube for the drive unit and plenty of room for lipo. Four 6S packs will reside inside the frame triangle while I am considering a bunch of 3S packs (configured in 12S layout) on each side of the frame with side covers to protect them. That will keep the overall width reasonable and give me plenty of range.
The drive will be a 4 turn 3220. This is the most powerful motor I have run that is absolutely 100% reliable. I could go higher power like a 6 turn Delta. But, that would be a bit too much power and would be a bit hard on the controller at partial throttle. This setup will be good for a reliable 9,000 watts without any reliability concerns. I honestly think I will need to dial out the wheelie tendency with the slipper clutch as it is.
Anyway, I will be working on this bike a little at a time over the next few weeks. I am guessing about 2 months to get it running.
Matt
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Hey Guys!
This started way back when I built the PK Ripper BMX bike. That bike was far more fun than any other bike I have built. However, it was too short (wheelbase) and had no suspension. I have had many requests for another 20 inch build and I began moving in that direction when I built the Cannondale Hooligan (Crimson) late last year. That bike looked to be a perfect candidate for an electric conversion. However, the lack of rear suspension was an issue as was the seat to rear wheel relationship. That bike is VERY wheelie prone. That is fine for pedalling, but not for high powered E-bike work. On top of all that, I had this Diamondback X6 frame sitting around (built by Intense Racing back in 99). This frame was bought for its perfect frame setup. There is room in the triangle for lipo and a high, round downtube for drive unit mounting. It also has a great swingarm for left side chain clearance.
That brings us to last week. My work has slowed down and I have been looking at various projects. However, money is tight. So, I did not want to buy anything new. So, I began doing some calculating and figured out that my X6 frame would work if I used a longer shock (I had one lying around) and flipped the shock linkage upside-down. This would drop the swingarm to the correct level for a 20 inch wheel (to have the proper crank height). So, I took my beat up X6 frame to the powder-coater for some gloss black and promptly disassembled my Crimson red Hooligan. Then I built up this bike with those parts and we have what you see here.
When I reconfigured the frame for 20 inch wheel use a couple cool things happened. First, the rear end is plenty long. This is great for a forward CG. It also rotated the frame forward, thus steepening the head tube angle. This sets up the geometry for proper road riding. I think the head tube angle looks a bit too steep. But, the bike handles phenominally like this. The wheelbase is also longer than my Hooligan (way longer than a BMX bike). This makes the bike far more stable while retaining sharp steering with the steep head tube angle. The forks are White Brother's Groove 180s shortened to 4 inch travel for me by White. The brakes are Hope 2 piston units. I may to to a 4 piston up front. We shall see. The wheels are Industry Nine custom items using my 47mm wide rear rim. I have another set of wheels like this that use standard spokes and hubes. I may use those and save these to put back on the red Hooligan as a peadl only bike. I have to see how things go with these wheels.
You can see the HUGE amount of room under the down tube for the drive unit and plenty of room for lipo. Four 6S packs will reside inside the frame triangle while I am considering a bunch of 3S packs (configured in 12S layout) on each side of the frame with side covers to protect them. That will keep the overall width reasonable and give me plenty of range.
The drive will be a 4 turn 3220. This is the most powerful motor I have run that is absolutely 100% reliable. I could go higher power like a 6 turn Delta. But, that would be a bit too much power and would be a bit hard on the controller at partial throttle. This setup will be good for a reliable 9,000 watts without any reliability concerns. I honestly think I will need to dial out the wheelie tendency with the slipper clutch as it is.
Anyway, I will be working on this bike a little at a time over the next few weeks. I am guessing about 2 months to get it running.
Matt