Engine Placement and Chain Length

Ken Bailey · Posted: Mon Jul 09, 2012 8:36 pm Post subject: Engine Placement and Chain Length

I am fitting out a 2011 CRG Blackstar with a Yamaha KT100. I am finding however that in order to have the motor mount sit perfectly on the frame without hitting welds for the Nerf carrier or crossmember behind the seat, I have to move the motor forward more than I am used to. This in turn is requiring me to run a fairly long chain. Is there a best practice I should follow that would help determine a starting point? Perhaps distance between drive gear center and sprocket carrier center?

I am fearful that if the engine mount lifts the even the slightest bit on one of the welds it won't be true and would cause the drive sprocket to be slightly off.

The mount is a Burris 5 degree. The 12 degree mount puts less of the mount in contact with the frame so that could be a partial solution but it really only gives me another 3/8's
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Walt Gifford · Posted: Tue Jul 10, 2012 11:16 am Post subject:

Standard length of 219 chain is 114 links, that's what I always use +or- a few if needed. That's with 10/86 gears.

Gif Cool

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Patrick Roth · Posted: Tue Jul 10, 2012 1:00 pm Post subject:

I try to line up the center of the motor mount clamps with the cross brace between the two frame rails that the motor mount clamps two. This allows me the flexibility to move the motor forward and backwards as required. I run a leopard with 10/82 and use ~110-111 links of #219 chain.

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Walt Gifford · Posted: Tue Jul 10, 2012 2:16 pm Post subject:

Ken Bailey · Posted: Tue Jul 10, 2012 2:22 pm Post subject:

Thanks for all the replies. I am starting with 10/80, and have the motor splitting the nerf brace so I can go forward or backward. It seems the nerf brace is just a bit forward of my old kart so it makes the motor seem like it is forward more than it should be. In reality, I put a new chain on and will probably have to shorten it by two links. Without counting, I would say I am at 112 links so am in the ball park by everyones comments.

Maybe the motor was actually furthur back on the old kart than normal and that is why I had a heck of time scaling up front.
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Muscle Cars, Guitar, Karting