New Build Question With SBP/5:1 Gearbox

[Deleted Member 4613]

5-7: If I wanted to go with all bicycle sprockets, where would I get the 10T drive sprocket that fits over the 5:1 gearbox? I don't see it on the dax part pages. Apparently, the 10T 6 cog drive sprocket is not commonly available and Dax only has a flat version (no neck), so using the Dax 5:1 gearbox would require drilling new hole patterns in the sprockets to fit the 8mm freewheel. The cvt option is looking far superior as a transmission, totally reliable, safe, and automatic.

 

[5-7HEAVEN]

5-7: If I wanted to go with all bicycle sprockets, where would I get the 10T drive sprocket that fits over the 5:1 gearbox? I don't see it on the dax part pages. Apparently, the 10T 6 cog drive sprocket is not commonly available and Dax only has a flat version (no neck), so using the Dax 5:1 gearbox would require drilling new hole patterns in the sprockets to fit the 8mm freewheel. The cvt option is looking far superior as a transmission, totally reliable, safe, and automatic.

Having never tried CVT, I can't really say drive which is superior.

10t drive sprockets are available at several scooter websites. Don't EVER use flat sprockets; there's not enough meat to keep the sprocket from wobbling on the spline.

 

[Deleted Member 4613]

I haven't found one so far. Scooter sites don't feature spline sprockets that fit a bicycle chain. None that I know of. They don't use bicycle chain, mostly 8mm. Got any links or sources?

 

[Deleted Member 4613]

This 5:1 gearbox is very cool. I opened it up to check it and it was filled with gear grease, good to go. I'm leaning strongly to use it for a light weight single speed chain drive using the double rightsided drive which brings the motor over the rear wheel for better balance and look. Don't believe this has been done before. Very simple and cost effective.

 

[5-7HEAVEN]

Yeah, I used to see a few 10t-6 spline sprockets for bike chains. Dax had both the junk flat one and the good ones.

 

[Deleted Member 4613]

Dax tells me they won't have anymore bicycle 10T drive sprockets for the 5:1 gearbox. They are switching entirely to 8mm sprockets which is great because they are more available.

 

[5-7HEAVEN]

Yes, that's great. Prices for 8mm T8F chain and sprockets are inexpensive and readily available. Since the links are more closely spaced than bicycle chain, the sprockets are smaller in diameter that bike or #35 drive components. My engine chainring is 72t, but it looks the same size as a 44t bike sprocket.

 

[Deleted Member 4613]

Here's a link to a 6 spline 12T drive sprocket that fits the 5:1 dax gearbox and would work with a bicycle chain. http://www.fancyscooters.com/item00298-scooter-part-sprocket-type-i-55-12-mm-12-tooth.html

 

[lowracer]

5-7 & @Deleted Member 4613,
Sorry if this thread is a bit old.
I recently received a 5:1 pocket bike gearbox w/10T sprocket which got my wheels turning.
I'm thinking of spreading an old MTB (100mm spacing) Cromoly fork to 135mm's & using a rear wheel as my front wheel. I have a 11-34 cassette and would just use the 34T. A track bicycle (fixie) chain fits the 10T & 34T. Correct me if I'm wrong on my math, if my engine turns 8500 rpm's, I divide it by 5 (5:1 transmission)= 1700 rpm's at the 10T. With a 26" wheel/tire I get 38-39 mph?
I like this idea for the freewheeling aspect. I have 2 MB's now (v-belt & friction drive) & neither freewheels. I think the freewheel will give better fuel economy & less wear on these wimpy clutches (not really designed to haul a man up to speed & engine brake).
-Lowracer-

 

[lowracer]

Here is a pic of what I'm thinking.
I spread the front fork blades slightly. The wheel isn't 135mm, but 120mm w/ a screw on 7 spd freewheel.
Will be pretty easy to make a rack for this setup using the long 3/8 axle to mount the upright struts & the cantilever bosses for a 2nd mounting point.
I think I have an spare Sram pc-1 chain around here somewhere...
Might even have to bust out one of those 3 pocketbike cags from storage since I'll need a bottom mounting point to mount the engine to the rack & I dont want to spend any money for this project.
-Lowracer-