Gary,
We used special PBI countershaft sprockets that I ordered directly from PBI.
These primary sprockets, 17-20 tooth, allowed the use of 530 chain on the '86
Kawasaki. The rear sprockets, 30-36 tooth, were standard bike shop stuff.
The chain was the "speed secret". For our first trip to the salt, I put in a
stock motor with PBI sprockets and Duckworth "racing" chain. We lubed the
chain before every pass and had to adjust it after every pass. Six passes
and the chain and both sprockets were completely worn out. I was in a bit
of a panic until I got lucky. I went to an all motorcycle drag race shortly
after Bonneville and asked everyone I could about chain. The universal
response was "use Tsubaki". These were Top Fuel racers including the
national record holder (who unfortunately got killed a few years ago).
So I got a Tsubaki 530 Sigma (O-ringed) chain and crossed my fingers.
The result amazed me. With the 200HP (estimate) turbo motor - no problems.
None.
When the chain doesn't stretch or wear, the sprockets don't wear.
I sent one chain back for analysis by the engineers in Japan. It had
13 full long course runs between 230 and 255 MPH.
They reported less than 10 % wear! Ten percent!!
Opinion follows.
8,000 RPM is pushing the envelope for the best steel bearings. 2 to 2.5
minuets is an eternity at these speeds. The problem I see is overheating
the oil. I would try a lubrication system using a very light synthetic oil
like synthetic ATF.
If you can afford it, ceramic bearings would probably be the best answer.
They worked well on the Thrust SSC.
All the best,
Bryan
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