jackshaft kit

I actually started pricing all the different components to build my own shifter kit and found that with the front freewheel system I was already more than half way to the price they were charging. That was about 8-10 months ago and they have come down a little on the price since then as well.

All in all I think it is a VERY good deal and only wish I had enough cash to get one myself.
 
its a good deal compared to other places that sell for higher prices.
if i could afford one, i would buy a jackshaft kit from sbp for that price,since they do include alot of parts and stuff for that price and after seeing a video of the jackshaft kit in motion.

sbp offfers great customer service too i hear.
 
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I played with my first china 40 tooth sprocket 5000 miles on it it was great I enjoyed it. The J shaft has been the most fun I have had with the china so far!
 
I finally got around to installing the shift kit from SBP that I bought two months ago. SWEET! I wish I would have installed it right away! One quick note though, be sure your derailleur is adjusted properly and mounted tight before you try it out with the motor. The mounting bolt for the derailleur had vibrated loose after 500 miles of motorized riding and since the only time I ever pedaled was to start the motor I never noticed. I started out in first, shifted to 2nd then 3rd and 4th. I am loving this thing! I was coming to a stop sign so I started to shift back down. Working beautifully! Hit first gear and Bamm!.bf. Derailleur right into the spokes and ripped it apart! Glad I was going slow! I had to laugh because I always meant to upgrade to a better derailleur when I installed the kit! Now I have a good one and I believe the shift kit is the ONLY way to go. So much smoother under power and coast. Now I don't have to wind out the motor so much to keep up with traffic. Best money I have spent besides my expansion chambers. I have got to get another. I always have one bike that vibrates more or won't keep up with the others.
 
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I got about 12 miles with my shift kit and loved it. I decided to get another. When I started the motor to go get the money order my free wheel locked up. I got it to free but one of the cogs must have broken. Sounds terrible, has a wobble, and catches every once in a while. :-||Anybody had similar problems with the standard freewheel going bad? I ordered another kit but got HD freewheels this time. 60 day warantee and it took me that long just to decide what bike to put it on! And I was having so much fun and taking it real easy breaking in this new motor. What did I do wrong?
 
You didn't do anything wrong than I am aware of, some last and some don't. We will still send you out a replacement if you want. Send me a PM or an email through our website and we will hook you up.
 
Just joined up and I've got a Mustang GTS stretch on the way. I really like the Jack shaft idea, and was thinking about maybe going with a 7 or 8 speed Nexus with it.
Any experience with the Nexus and this kit? Think it will hold up to the power of a 66 Skyhawk or the dax F80 and will the kit fit both of these motors?
 
The kit will fit both of those engines.

From what our customers have reported the internal hub transmissions are hit and miss. I think one in good shape and shifted correctly will work fine. I think most of the ones customers had issues with were old, not maintained or simply abused.
 
Sounds good. I'd go with a brand new hub. I saw an 8 speed nexus that had better berrings etc. and was only a bit more expensive so I'd proably go that route.
I also noticed that the bikes that have your kit have the engine mounted back in the frame to the seat tube. Looking at the Mustang GTS on the banner the motor is up toward the down tube. One on Zone 8 has the motor mounted back toward the seat tube, but neither have the jack shaft kit. Is one mounting location going to work better than the other for the Jack shift kit?
 
I took a look at the bike and unless you can do some welding it will be difficult to adapt the kit. You can weld in a secondary downtube for the front engine mount. This will work but will require some adaptation as the chain line from the jackshaft to the bottom bracket will be different. It has been done on other "chopper" style frames so it can be done. The other option is to weld in a secondary seat tube. This would probably be the best option. The chain line would be correct and the engine would sit a little farther forward which I think would look better.
 
Thanks for the help.
I'll probably just go with the normal set up at first then see how that works for me. I got the matte black frame though just in case I need to do some fab. work on it (plus I heard the welds are pretty junky on these frames) I won't have to mess up a pretty paint job until it's done.
 
You may be able to do something like I did on my Stiletto. I attached a picture of the motor mount which could be extended to incorperate a jackshaft. Might give you some ideas. I know where you can order all the parts you would need to make a mid-frame jackshaft. usflg
 

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im planning on building a bike with a shifter kit for the summer, iw as just wondering if these kits can take a beating, i only ride my bike i prefer it over the bus and sometimes i push them beyond limits, i just finish building a 66 cc engine i just threw in SKF bearings wicha ran me like 30 buck and the engine seems to be running very good and im scared to run a jackshaft kit in the winter for reliability concerns, so far ive only herd good things about thenm but had anyone had any issues with them so far?
 
spit_fire said:
im planning on building a bike with a shifter kit for the summer, iw as just wondering if these kits can take a beating, i only ride my bike i prefer it over the bus and sometimes i push them beyond limits, i just finish building a 66 cc engine i just threw in SKF bearings wicha ran me like 30 buck and the engine seems to be running very good and im scared to run a jackshaft kit in the winter for reliability concerns, so far ive only herd good things about thenm but had anyone had any issues with them so far?
Click to expand...

The kits are very well built. You should consider the heavy duty freewheel, which might be the only weak part of a standard kit. I carry a spare drive side chain cause that is the only part that I have ever broke, and it is not part of the kit, it got wrapped up in the sprockets.
 
witch would be faster a jack-shaft kit or just a 36-50 tooth sprocket? im building my first bike from a PK 50 motor and that's one of my major questions! i just switched from a Indian moped (cant find parts) to this bike project so i want it to go 40-50mph range (even just 40mph is fine) xct2.xx.

b.t.w its a mountain bike 26inch (i think) :-||
 
The speed will be the same, same ratio, same speed. But if you gear tall to go 40 mph then you will probably have to pedal up to 20 mph before you can engage the motor because it is geared so tall. Climbing hills will also almost be impossible with that tall of gearing. This is the beauty of the Shift Kit. You get tall gears for going fast and low gears for acceleration and hill climbing. BTW 40 mph is nearly impossible with a stock engine. It simply doesn't have the horse power to go that fast. Wind and rolling resistance are hard to overcome at those speeds without lots of horse power.
 
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