Transmission Gear Change

[alhall88]

I'm not sure how you guys like the newer DD6 gearing but the OD6 needs a little refinement. I have a couple calls out but it looks like the OD6 uses a 32 sprocket and I'm working out on which one I would like to switch to. Baker claims a 7% increase in torque with a 30 tooth and 10% increase with the 29 tooth pulley. I'm only looking at a 300 rpm increase at 75 mph. The big question I wonder is how far can I go without changing the belt. I have already checked the new S&S belts and found that they do make a 128 tooth belt which is obviously shorter than the 130 tooth that I run now. I'll get a call into baker and see if they have some type of chart that would show what I need unless you guys have an idea????

Looks like I found my answer. For every tooth change you need 1/8'' of adjustment. Here's a little chart I found.
Andrews Products - BIG TWIN TRANSMISSION BELT SPROCKETS Fits all EV80 and Twin 88 5 and 6 speed transmissions

 

[MARV]

ah a tech thread!

found some sheets from 3/06 when i was doing a trans sprocket change.

couple of ways to change the final drive ratio.

engine sprocket/clutch sprocket

trans sprocket/rear wheel sprocket

good thing about the OD6 is it is actually an overdrive 6th gear were as the BD DD6 is a 1 to 1 6th gear. so me raising my final drive ratio to 3.40 is great off the line but not at high speeds.

also with the 05 it has the 29 engine sprocket and 43 clutch. then my 24/50 final chain.

not sure about the 04's


RB has a calc

Drivetrain and Speed Calculator

 

[MARV]

check that:

25/50 after my HHI sprotor set-up

 

[alhall88]

Thanks marv I did check out the R&B calculator and already looked at my options with the gearing on the belt drive that I'm running and the cheapest way to accomplish this is the trans pulley and belt if needed. I'm looking at the long life steel trans pulley but wonder about the aluminum race pulley and if its worth the extra coin.
BAKER Drivetrain | Premium Drivetrain Upgrades | Transmission Pulleys

 

[MARV]

here's a curve ball


with that W9F maybe you should jump to this


Product List

 

[Vegas]

Hell yeah.....left side drive should really simplify a chain conversion. You could play all day long that way. At least there are 2 tech guys left. :roll: I haven't been bitten by the bike bug yet. Would like to build my own one day though. I just know how I am and what it would end up costing!

 

[MARV]

I haven't been bitten by the bike bug yet. Would like to build my own one day though. I just know how I am and what it would end up costing!

buy a manual first! :roll:

 

[Vegas]

Where is the middle finger icon? Wouldn't need one for the bike I'd build My bike has been setting on the stand with the front end ripped off for weeks. I had to finish my car for my march feature. Plus it's only in the 60's. Shit...I'll freeze.:roll:

 

[MARV]

i'd suck mother nature's ass for 60 degree weather!

been so cold here i actually cleaned the bike, chain, adjusted the shocks, installed Jakes HID, even waxed the fuckin thing!

come on spring!

 

[Vegas]

Bull shit....I've never met ya but I have you pegged for one of my buddies that washes it once a year if the bikes lucky.

 

[MARV]

hey i don't lie.... to men. :up:

since i havent lost any weight i figured if i cleaned it it might be faster!

 

[lee]

Hey Al I am completely ignorant on this topic but do you not have enough play in your rear wheel adjustment to save having to get a new belt? Might be a stupid thing to say.

So Marv you caved in and cleaned your bike...all my illusions have been shattered

Remember gents - bling is bad, performance is good!

 

[alhall88]

Hey Al I am completely ignorant on this topic but do you not have enough play in your rear wheel adjustment to save having to get a new belt? Might be a stupid thing to say.

So Marv you caved in and cleaned your bike...all my illusions have been shattered

Remember gents - bling is bad, performance is good!

Lee according to the formula it looks like I would need 1/8 inch of axle adjustment for every tooth reduction. Based on that it looks like I only have enough adjustment left to accommodate a 1 tooth reduction which is not enough for me. Looks like a belt replacement and sprocket or a total chain conversion which at that point I think I would have to replace the hub. I was thinking I was done with this bike but guess not. Give me a couple weeks to get everything priced out and if the weather still sucks here I may do it. Being layed off lately every month for a week or 2 is really cutting into my bike fund.

 

[alhall88]

So it looks like my current setup is a 3.215 final drive ratio. Dropping the trans sprocket from a 32 to a 30 will change the final to 3.429 and if I go to a 29 trans sprocket the final would be 3.548