Motorcycle Racing Forum

Racing Discussion => Racing Discussion => Topic started by: the_blob on September 23, 2005, 05:59:55 PM

Title: yoshimura cams for GSXR
Post by: the_blob on September 23, 2005, 05:59:55 PM
what are the advantages and disadvantages of installing aftermarket cams.
particularly stage one yoshimuras in an 04  GSXR1000??

any advice would be greatly appreciated.

thanks

Title: Re: yoshimura cams for GSXR
Post by: Super Dave on October 09, 2005, 03:30:52 AM
Probably has longer duration for more time to bring in an air/fuel mixture and then more time to let out the exhaust gases.  

I'm assuming that a stage one set up might have stock lift as, I believe, the AMA rules don't allow anything more than the stock lift.

Disadvantages?

Some Superstock bikes are producing nearly 190 RWHP.  They have traction issues.  Liter bikes spin the tire on the banking at Daytona in 6th gear.  Not sure why you'd need more.

You'll have to have the cam timing redone, and probably a new fuel curve.  
Title: Re: yoshimura cams for GSXR
Post by: damico on October 20, 2005, 12:54:50 PM
I would contact Greg Moon at Moonlight supercycle he has done the testing and knows what works on those things. If I remember correctly gsxr1000 are pretty sensitive to cam changes(ie it dont work). Call Greg he will give you the skinny your looking for, and besides knowing his sh*t he is staight forward and trust worthy. Yes, there still are a few mechanics like that.
Title: Re: yoshimura cams for GSXR
Post by: WebCrush on October 22, 2005, 12:02:48 PM
I had an 04 1000 and put the WebCam 540/566 grinds in.  I never had it dyno tuned, but it had lots of grunt and good top end as well.

And yes, I had the rear of the bike step out on me at Daytona halfway around the banking.  

Be careful.
Title: Re: yoshimura cams for GSXR
Post by: Xian_13 on October 24, 2005, 02:52:30 AM
QuoteI would contact Greg Moon at Moonlight supercycle he has done the testing and knows what works on those things. If I remember correctly gsxr1000 are pretty sensitive to cam changes(ie it dont work). Call Greg he will give you the skinny your looking for, and besides knowing his sh*t he is staight forward and trust worthy. Yes, there still are a few mechanics like that.


Its Moon Super Cycle (not moonlight).
Yes, he is a knowledgible guy on all modern sport bikes.
His phone number is Above the dancing girl.

XIII
Title: Re: yoshimura cams for GSXR
Post by: mdr14 on October 24, 2005, 10:53:29 AM
I have just seen mostly a moderate midrange and top end increase with the Yoshimura Stage 1 cams. We also saw a decrease in bottom end power. this is with stock motors and cams dropped in and degreed to proper lobe centers.

Sometimes on a 1000 it is possible to come out of a corner quite low in the engine rpms. You may loose some of the off the corner grunt in those situations.

When I have raced with guys that did have those cams, I killed them off the corners. At Road AMerica they would have a slight advantage top end...It ends up being a wash at that track.



Title: Re: yoshimura cams for GSXR
Post by: JBraun on December 20, 2005, 08:59:31 AM
I have the same bike and I'm thinking about putting 600 cams in it, or maybe a 600 motor. Maybe I'll unplug a coil... ;D
Sometimes I swear I could go faster if the bike made less power and didn't try to kill me....
Title: Re: yoshimura cams for GSXR
Post by: Super Dave on December 20, 2005, 09:16:42 AM
LOL!  Yeah, you are probably on to something....
Title: Re: yoshimura cams for GSXR
Post by: Thingy on December 20, 2005, 04:24:49 PM
I'd second that! :o