Author Topic: Seeking 500/550 Turbo Motor Advice  (Read 1134 times)

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Offline Greggo

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Seeking 500/550 Turbo Motor Advice
« on: April 14, 2012, 11:41:12 AM »
I'm one trip to the shop away from finishing my 750, so naturally my mind has moved on to the next project...a turbo motor for my 500/4.

My objective:

Build a reliable, low boost turbo 500/4 motor for my (almost) daily rider.

Here's what I've got:

ATP turbo kit w/original Rajay unit, and Solex carb.
CB650 cam shaft.
An oil cooler kit w/filter adapter.
I have two choices of motors, both '71 500/4's, one in my current bike running, the other needing rings.

My Questions:

Will a 650 cam work well with a low boost turbo? 

Will I need forged pistons for this type of set up?


Here's my set up.  The header needs some work, but it's not that difficult to fix.




« Last Edit: April 14, 2012, 08:34:45 PM by Greggo »

Offline JLeather

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Re: Seeking 500/550 Turbo Motor Advice
« Reply #1 on: April 14, 2012, 04:46:08 PM »
Greggo, according to Mr Turbo's old literature on these kits a bone stock motor oughta be fine for 5psi or more.  That's not even changing the timing.

Check out this old CB550 turbo install article:

http://s86.photobucket.com/albums/k113/JLeatherman_CF/Blog%20Pics/

Offline Greggo

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Re: Seeking 500/550 Turbo Motor Advice
« Reply #2 on: April 14, 2012, 05:11:55 PM »
Thanks J!  That pipe cleaned up real nice. 

« Last Edit: April 14, 2012, 05:14:09 PM by Greggo »

Offline JLeather

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Re: Seeking 500/550 Turbo Motor Advice
« Reply #3 on: April 14, 2012, 05:48:53 PM »
Wow, it sure did!

Offline Greggo

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Re: Seeking 500/550 Turbo Motor Advice
« Reply #4 on: April 14, 2012, 07:18:55 PM »
As far as the cam goes, I have a nice stock early 550 cam.   But, the 650 cam gives a nice boost to my current 500 in the mid range.  Would that characteristic be desirable in a turbo set up?