Overdrive 5th gear

I run a bit more swingarm angle to get proper handling so I can never get the chain off the shaft. I also run the tall 5th gear to be able to run a larger rear sprocket to get the chain off the top of the swingarm pivot. My bikes are pretty far from stock so my situation is a bit different.

What I need to do also is put a hydraulic set-up on the other side of the engine and plug the clutch pushrod hole and run a 19T sprocket! Need more top end outta these things.

If I run a larger rear sprocket, it lowers my gearing but gets me some swingarm clearance. I need to re=gear the primary. That would fix everything!
 
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- a RHS pull hydraulic clutch?...that would be interesting...i have seen honda RHS cable operated pull clutch mechanisms modified to do this...i can visualise how hydraulic could be made to work and wonder whether any manufacturers already do this
 
- if i understand correctly he wants to incr the gearing by removing the clutch pushrod and installing a larger front sprocket...one of ivans high ratio gear sets would help here too...and gain a little more clearance over the swingarm pivot?
 
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inxs said:
- if i understand correctly he wants to incr the gearing by removing the clutch pushrod and installing a larger front sprocket...
Click to expand...

I understand that INXS, Trying to find out what he has done and what he is trying to achieve
 
By raising the swingarm pivot (what I'm trying to do), relative to a line between the center of the countershaft sprocket and the center of the rear sprocket(rear axle), it plants the tire under acceleration. In dirttrack, this equals drive versus tire spin. Good for starts and leaving the line. On the road, it equals acceleration instead of power being sucked up by the suspension action. Stock or in the chopper fashion, lowering the s/a pivot decreases traction and makes the rear of the bike squat (At the seat) and it wants to lift the wheel off the pavement. Thats commonly referred to as an undesireable situation.

So to answer your question, I'm trying to achieve improved handling and traction.
 
So by raising the swing arm pivot you need the 19 tooth front to help you clear the swing arm ? ......I reread you post and i get what you are doing now you have edited your post, you first said you wanted to get more top end and i couldn't figure how the 19 tooth front was going to help much with a stock crank
 
The racing primaries that Ivan Hoey has had made, He recommends a 17/36 gearing for a road XS.....18/34
 
650Skull said:
So by raising the swing arm pivot you need the 19 tooth front to help you clear the swing arm ? ......I reread you post and i get what you are doing now you have edited your post, you first said you wanted to get more top end and i couldn't figure how the 19 tooth front was going to help much with a stock crank
Click to expand...

Depending on which swing arm your using or if your using a stock unit,any swing arm degree of 8 or higher,you'll pull the chain closer to the swing arm pivot causing the chain to rub. Most sport bikes swing arm degrees are set around 13 to 15 to aid in keeping the steering rake geometry stabilized under hard acceleration,road pavement conditions and to slightly pull the rear tire down to keep the power planted where it belongs. If you have provisions for a rubbing block near the swing arm pivot point,a rubbing chain isn't a concern as most sport bike chains glide across the top of swing arm. I have mine set up in my on going project at 13 degrees. If you want a motor to pull harder on top you either increase the power output or displacement and keep the motor in it's prospective powerband where it pulls the hardest on top and if it produces sufficient torque,then one might consider raising the tooth count but I've ridden a few XS where the gear ratio was lowered and those combinations are not my cup of tea.
 
- tilting the motor slightly forward would achieve this too by raising the centreline of the gearbox output shaft
 
tilting the motors center of gravity forward will drop counter sprocket CL,new back mounts will be in order to bring the back end of motor up to reline the CS center line to it's original position,have mine tilted 13 degrees in a FZR frame.
 
- the cl is only going to drop if you tilt from the rear mounts and that doesnt work in an xs frame very well as it lowers the bottom mount and gives clearance problems with the crankcase...i dummied it up this afternoon and got just under a 1 cm raise in cl with about 8° tilt
 
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In response to Skull


If the chain "Glides" accross the top of the swingarm, this IS a concern as the top of the chain is like a harp-string under power. This will wear through a slider block quickly and then into the swingarm, which is highly undesirable!

SKULL-"If you want a motor to pull harder on top you either increase the power output or displacement and keep the motor in it's prospective powerband where it pulls the hardest on top and if it produces sufficient torque,then one might consider raising the tooth count but I've ridden a few XS where the gear ratio was lowered and those combinations are not my cup of tea."

This is apples and oranges. Having a higher overall gear so the engine isn't screaming it's guts out on the freeway and having an engine make more topend power are two totally different topics. Having done all the common power upgrades will not change the engines gearing. It WILL make it rev out with it's current gearing quicker. That's why you strive for more power.

My dilema is that I want more chain to swing pivot clearance. The only way I can lift the chain upward is with larger sprockets front and rear. You are aware of the front clearance issues inherent with the engine design. My point is that going to a 40-46 on the rear will lower the gearing so much it would be speed limiting and although I've installed the 5th gear set from Mikes in 3 engines, they are in bike projects that haven't been ridden yet, so I'm not sure if they'll make a big enough difference.

Sportbike stuff doesn't reallyapply as they have alomst limitless front and rear gearing options with no clearance limits!


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Then wouldn't a set of racing primaries be the answer coupled with an increase in sprocket size. As the RP are about a 20% reduction then you would be able to get the larger sprockets you need for your clearance
 
Mule, on the editing feature it gives an opportunity to explain why the editing was done. you edited after my initial question and then i understood what you were trying to achieve.

Is the swing arm shorter or is that due to the angle giving it that look. How much has it shortened the overall length
 
mule, what wheel are you using on the rear? I see it has spokes and a disc brake.
 

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