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Old April 27th, 2011, 07:06 AM   #31
Lowspeed Lowside
Tightwad Tinker
 
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Name: Hans
Location: Lexington, Ky
Join Date: Apr 2011

Motorcycle(s): '09 Ninja 250R

Posts: 161
Quote:
Originally Posted by Racer x View Post
the RHB 31 is very small perfect for a 250 four stroke.

http://www.chinese-parts-canada.com/...injection.html
I remember seeing that! I think the RHF3 and RHB31 might actually be very similar. Too bad we can't find compressor maps, so that we can compare them.

I'm not convinced that bolting on the turbo as close as possible to the engine is necessarily optimal. While it is true that we are trying to avoid cooling off the air and wish to preserve the pulses, I think it is worthwhile to consider using two straight pipes (with 125cc volume each), before we merge and direct into the turbine. The idea is that we leave enough room for the exhaust pulse to go so that we avoid closing the exhaust valve with hot, compressed exhaust gases still trapped in the chamber. If fear that would aid detonation and decrease the amount of unburnt fuel that can go into the camber the next cycle.

Something else ... a KP35 could fit your purposes, maybe better. If you look at the compressor map



you can see that at 1.2 bar overpressure (16 PSI) and 0.56l/sec (120bfm) you're splat in the middle of the efficiency island, (maybe ~40-50kw). It's $243 shipped (http://www.aliexpress.com/product-gs...olesalers.html)

For our <$1000 experiment the KP35 is possibly a little too big. Could be good for a non-aggressively souped-up Ninja 375R?

Quote:
Only problem so far is the clutch . I fixed that with beefer springs. I did have some engine damage but that was totally my fault . So far this year no problem .
What springs did you use? We're on a budget and will need a cheap source. $10 here, $10 there, adds up quickly.

Quote:
Originally Posted by Alex View Post
Less talking. More building.

(with video. )
Put your pantyhose back on! It's a project for next winter! You'll catch a cold!

Just out of curiosity: if the necessity of a group order arises, would you be interested in owning a turbocharger-shaped paperweight, that just might have a motorcycle-related purpose?
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