Timing cams...Q&A

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Killerwhale
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Timing cams...Q&A

Post by Killerwhale » Sun Jun 14, 2009 9:26 pm

So, i need to set the cams to 105,5 inlet and 106,4 exhaust...
Is there a nice formula one can use to calculate how much to retard the cams...in degrees?
...or should i go buy a gauge and do the whole thing from start?
...or just go by feel?

From standard 105 to 105,5 it can´t be much that should be backed up on the inlet but on the exhaust it´s quite a bit from 109 to 106,4.
Overlap should increase quite a bit anyway....

Your thoughts??

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steve speed
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Re: Timing cams...Q&A

Post by steve speed » Sun Jun 14, 2009 10:21 pm

didnt Hans do all this ?? and ended up back to std ?
TRX850 ,The thinking mans R1

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dandywarhol
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Re: Timing cams...Q&A

Post by dandywarhol » Sun Jun 14, 2009 11:12 pm

1996 TRX 850, blue, Ohlins 46HRCLS, Race Tech Gold Valves, 0.90 springs, Venom pipes, R6 brakes............
1974 Yamaha RD250A, Candy Blue
1998 Yamaha SZR660, blue of course
1967 Yamaha TD1C 250, Blue and white

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Killerwhale
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Re: Timing cams...Q&A

Post by Killerwhale » Mon Jun 15, 2009 7:03 am

steve speed wrote:didnt Hans do all this ?? and ended up back to std ?
Nah i think you remember first time around when i used a tuning garage in the south of Sweden, to my knowledge Hans has never used slotted sprockets....!?

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Killerwhale
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Re: Timing cams...Q&A

Post by Killerwhale » Mon Jun 15, 2009 7:05 am

dandywarhol wrote:I've always used a degree disc.

This any use? P43 details timing http://www.kentcams.com/Downloads/Files ... lowRes.pdf

http://www.minimania.com/ArticleV.cfm?DisplayID=1767
Cheers...
Can one say that if you move the lobecenter 2,6 degrees back it´s on the crank so you actually have to take half that!?

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dandywarhol
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Re: Timing cams...Q&A

Post by dandywarhol » Mon Jun 15, 2009 10:39 am

All settings are taken from crank degrees
1996 TRX 850, blue, Ohlins 46HRCLS, Race Tech Gold Valves, 0.90 springs, Venom pipes, R6 brakes............
1974 Yamaha RD250A, Candy Blue
1998 Yamaha SZR660, blue of course
1967 Yamaha TD1C 250, Blue and white

HansJ
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Re: Timing cams...Q&A

Post by HansJ » Mon Jun 15, 2009 3:25 pm

I actually had slotted sprockets, but initially set all at standard timing. Then the nightmare started with the worn down cams, pitting, stolen crank etc, so I never got to do any serious testing. And I had Kent cams, which "should" be set as standard (although my tuner urged me to do some testing). This winter latest, will I carry out some more testing. A degree wheel is essential, and a micrometer gauge with a good magnetic stand is also needed...
IQiokW
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