Hi,
I race a formula 2 sidecar that is running R6 13s engines. Last year I had a crash and the outfit ended up upside down, the engine was running upside down for a short time so I decided to rebuild it. I have purchased new main and big end bearings and rebuilt the engine, however the crank is very still to turn with a ratchet. I have split the casing again and there is definitely binding happening on the main bearings.
I have a copy of the 2008 service manual and followed that when rebuilding. What I am confused about though is the tightening sequence of the crankcase bolts. I also have a kit manual and can see that the sequence is very different, and the final angle stage is missed out.
From the 2008 Service manual I have
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From the 2010 Kit manual
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So it looks like the final angle is not done? This appears to be the same in the BN6 manual also, no final 70 - 80 degree tightening.
If I tighten the bolts up to the 3rd stage, it still spins freely by hand, only when I tighten the further 70 - 80 degrees does it start to bind.
I am led to believe this engine has a GYTR crankshaft but I am not sure how to confirm, that's why I was looking at the kit manual also.
I have a single number 5 on the crank cases (This means all are 5 right?).
The crank is stamped 1 2 2 2 2. So I ordered 2 brown mains for closet to the flywheel and the rest are Blacks.
Anyone have any ideas?
Thanks,
David
I race a formula 2 sidecar that is running R6 13s engines. Last year I had a crash and the outfit ended up upside down, the engine was running upside down for a short time so I decided to rebuild it. I have purchased new main and big end bearings and rebuilt the engine, however the crank is very still to turn with a ratchet. I have split the casing again and there is definitely binding happening on the main bearings.
I have a copy of the 2008 service manual and followed that when rebuilding. What I am confused about though is the tightening sequence of the crankcase bolts. I also have a kit manual and can see that the sequence is very different, and the final angle stage is missed out.
From the 2008 Service manual I have
From the 2010 Kit manual
So it looks like the final angle is not done? This appears to be the same in the BN6 manual also, no final 70 - 80 degree tightening.
If I tighten the bolts up to the 3rd stage, it still spins freely by hand, only when I tighten the further 70 - 80 degrees does it start to bind.
I am led to believe this engine has a GYTR crankshaft but I am not sure how to confirm, that's why I was looking at the kit manual also.
I have a single number 5 on the crank cases (This means all are 5 right?).
The crank is stamped 1 2 2 2 2. So I ordered 2 brown mains for closet to the flywheel and the rest are Blacks.
Anyone have any ideas?
Thanks,
David
