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Denis J
Denis J
Sacramento, CA
Posts: 396
Joined: November 2012
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Thread Like Summary
Allan G, Nick H, Tigernuts
Total Likes: 3
Original Post (Thread Starter)
by reverb


-70-9989 ex at factory mark with intake at factory mark.
-70-9989 ex at factory mark with advanced intake like Mr Russell suggested at some point but is a bit unclear for me.
-709989 ex at another mark and factory intake mark. Something that I do not know if can work.
Liked Replies
by Mike Baker
Mike Baker
Do you have the cases split? A 650 exhaust cam will make a noticeable difference.
My go to cam timing is around 101 degree lobe center intake and 105 degree exhaust. Seems to make good power where needed most. Unless you check, you will not know what you have. Just moving gears around could be an exercise in frustration.
Most 650 ex cams I've checked clock in at about 98 degrees stock marks. Most 750 ex cams are more like 92. Either would benefit from moving to 105 more or less in my opinion.
My 650 desert sled was assembled on the stock cam marks. Put down a whopping 29 hp. Ex cam was 98*. Moving it to 104 saw an increase to 34 hp on the same dyno. The power is in there somewhere, you just have to find it
1 member likes this
by TinkererToo
You really MUST have the extractor/assembly tools, particularly the assembly one, or you will damage the camshaft bush with the camshaft key. Send me an email, and I'll send you a reasonably simple procedure for setting the cams using lobe centres. Usually the inlet cam will be about right with the standard marks, but not the exhaust, but best to check
1 member likes this
by DMadigan
Mick, I do not want to pick apart whatever method you have.
If you have symmetric lobes you can rock the cam between the two cylinder lobes and split the difference. then you are 90 cm degrees from lobe centre. By counting pinion teeth you can figure how far the crank has to be turned before inserting the intermediate gear. Or leave the crank gear at TDC and rotate the cam gear the required number of teeth.
1 member likes this
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