1. C

    Need help getting a good gear ratio

    I'm currently building a 125cc 4 speed manual motor onto a bicycle but I'm unsure what sprocket sizes I should chose. I want to have a decent amount of top speed (80kmh should be easy with a 4 speed transmission) but still have acceleration around the city. Any help is appreciated.
  2. B

    Need help! 140 spoke rims and installing the rear sprocket

    Hey guys, need some help here. Just a got a new bike and I mainly bought it because I loved the rims on the bike. The rims have 140 spokes and I really didn't think about how to install the rear sprocket before I bought it. Anyways, I have a pic of what it looks like below, but my main question...
  3. L

    Climbing hills, real ones.

    Howdy, 1st post and happy to finally join! Wasn't sure where to post this, as I'm new, but here we go. I've been interested in making a fresh hill climber for hiking/mountain bike/dirt bike trails. I am chill as a cucumber if I can't go faster than 25mph max speed, as I know with these...
  4. S

    Will a 68T Sprocket from Wish fit with the chain and mounts of a 2 stroke kit?

    Im planning to buy one of these cheap chinese 2 stroke kits. I know they are pretty low quality and require regular maintence. I live in a village with many hills and bumpy roads and i like going off road. I found an 68 tooth sprocket on Wish but im not sure if the chain and sprocket mount are...
  5. S

    O ring keeps popping off rear wheel hub

    Hello, I have a 66cc two stroke engine on a hyper cruiser bicycle. It went great for the first few miles but now the o ring keeps popping off the rear hub releasing the bicycle sprocket and I can’t pedal or stop (using coaster brake). I reseat it and it pops off within minutes anyone have any...
  6. ilandz

    Many problems with chain drive system...

    I'm very new to motorized biking, having just finished turning an old 90's mountain bike into a speed demon. (or at least I hope it will be) The kit I got was a pretty standard 49cc 4 stroke from ebay. The biggest problem I've had so far is the chain that connects the belt drive to the sprocket...
  7. Memy1251

    Drive sprocket won’t turn

    So this is my first build, and once it was all together, I found that on disengaging the clutch the bike would not roll but what little slack the chain would allow before the chain would run out of play and snag. I’ve gone through clutch re-set and cleaning procedures, such as cleaning the pad...
  8. U

    Building A Motorized Bike (New Here)

    Hello There Everyone the names Amir and I'm new here :D (This is going to be a pretty long post, BUT I would really appreciate if you could read it, If not go to the end where I bolded everything) So let's start off, Since last year ago I have been looking over YouTube and forums on building...
  9. Lenamarie81

    Chain broke how do I get it off the clutch sprocket it is hard .

    My chain broke I'm in the process of installing a new one how do I get the chain off the clutch sprocket help please!
  10. S

    Needing a hub mounted sprocket for .8" to 1"

    Okay. So I've tried searching a bunch on many forums and sites and k I can't seem to find anything that will fit my Raleigh USA Heat. The rear hub is little less than an inch and most hub mounted sprockets from anywhere only seem to goto and inch or more. Curious if anyone knows of one I can get...
  11. T

    Looking for replacement sprocket for HuaSheng 49cc transmission

    Need a replacement sprocket, but am having difficulty finding one that fits this type of shaft. Please let me know of anyone who sells this sprocket or this transmission . Thanks.
  12. H

    Pedals are locked up

    I bought a motorized bike recently and its been great, my friends and i love to ride them around due to our town having a lot of bike lanes. I've run into a problem with my chain/sprocket. When i try to turn my pedals the wheels and chain refuse to make a full turn. I've read through some other...
  13. B

    Sprocket adapter for Shimano FH-RM30

    Do you know where i can find an adapter for my Shimano FH-RM30 rear hub? It must be okay with a 36T sprocket. Bolt circle diameter: 45 mm Flange diameter: 53,8 mm Spoke holes 36 holes .spr.
  14. S

    Newbie Gearing Question

    Have a HF 79cc going on a bike with 26" tires. Engine will be keeping the governor so 3600-4000rmp (gov tweek if I can figure that out). Thinking of running a jackshaft with 11 tooth clutch, 22 tooth input, 9 tooth output, to a 48 tooth rear. If I figured right should be a 10.67 final. Will...
  15. W

    Has anyone used the new Wheelset by one of the forums advertisers?

    Hi All! :) Long time that i've posted here ... http://www.kingsmotorbikes.com/cnc-aluminum-wheels-silver.html I'm going to call next week and find out specifics, but it does look good. Has anyone used this? Can anyone give a review? Thank you.
  16. M

    Order of rear sprocket assembly?

    I have the standard sprocket assembly for my rear wheel for my 66cc engine kit. Instead of the metal sprocket being the most exterior line of things in the order on the back wheel, one of the rubber things is outside on the other side of the sprocket, and the sprocket is in between two of them...
  17. TheNecromancer13

    Chainring Bolts Unscrew Themselves Like Clockwork

    So I have a rear sprocket attached to an adapter that mounts onto a disc brake mount, and the chainring bolts that attach the sprocket to the adapter keep unscrewing themselves no matter what I do. I used threadlocker on them last week, and they still unscrewed themseves! They do it within a...
  18. Patchy

    Kickstarting a China girl

    http://youtu.be/ZF2eAiXBOrw I can kick start my bike now! Got a new 36 tooth sprocket, removed my broken shifter and put my regular bike chain on the lowest gear. No more annoying petal starts! On a side note, clean your chains. All the goop is from both my chains.
  19. C

    need for speed

    i am using the sprocket that comes with the chinese 2 stroke. and i can only reach 32 mph in a straight road. i am going to also be carrying replacement parts, 1 gallon os gasoline, headlights breaklights turn signals rear view mirrors and a bike rack, and i want to make atleast 40. the best...
  20. jolfstn

    Fat Tire & Clearance issue. Traffic, hills, and rambling questions

    This is my 2nd build, and I purchased this as the bike base: This issue is the 3" wide tires, which I'm sure will go far as smoothing out the ride goes, however, the standard spoke mounted rag joint doesn't have the necessary clearance. I've tried turning the sprocket over so the teeth are...