Yes I worked with Jim at JL for a couple of years before I went to work with Hines at Zipkart as factory manager.
Even now Jim has his minions cut patterns by hand as his labour is cheap, lasers cost a fortune, plus the needed CAD packages/operators to suit.
One thing I have mentioned several times here is that the reliability ( or lack of it ) of the recently powerful buckets has nothing to do with the design philosophy
or even an inherent 2T issue.
Its all to do with knowledge base and implementation.
TeeZees thing would never have died , if I had seen the ignition curve before the problem became very publicly obvious ( and you have to admire him and his team showing the world what not to do for free, even
though it costs those guys plenty in time and parts ).
Building a 4 speed is just as easy as building for a 6 speed.
You just plug in the bmep numbers and by default the lower requirements will produce a wider powerband.
Same with the pipe design ,the angles and relative % lengths needed to give as wide a band as is required to stay in the power , its simply a different approach to tuning for high bmep and thus power peaks, at
the expense of width.
Depends at the end of the day on the funds available.
With plenty of cash I would always go for the fattest torque curve with the rpm up near the cranks mechanical limit of say 14000.
This approach with a ton of rpm and a wide powerband will always be faster than the same engine developing its power down at 10500,with the huge advantage of adding several teeth on the
rear sprocket and the physics of torque multiplication, plus the vastly superior sonic tuning available with that higher rpm.
But to use that approach requires a heap of detailed knowledge,and of course that costs money, as anyone can read Bell and Jennings, then build a bucket with good power at 10500, but that
is no longer an option with 30 Hp easily doable - just the finer points need to be addressed and those guys will be GONE, 20M ahead at the first corner.
PS - if ANYONE can do a 125 Aircooled with 24mm carb and make anything like 30 Hp at 10500, then its here in writing - free blowys for life.
Ive got a thing thats unique and new.To prove it I'll have the last laugh on you.Cause instead of one head I got two.And you know two heads are better than one.
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