yoshimura cams/ cam chain length

[Steveb64]

the bike was built for the world formula one champs in the early 80's with the monocoque chassis made entirely from carbon fibre, a world first. its a hot rod engine and with the yoshi cam set up needs the idler between the cams built into the rocker cover.
this however leaves the cam chain real tight with a standard 120 link one and therefore someones fitted a 122. this has led the cam chain to be real loose and out of touch really with the standard tensioner, or too tight with 120 links.

what i'm looking for is anyone who has this set up and what they found with their cam chain


how does one post a photo?

Is that one of the Steve Roberts ones? ... I've got a single shock McIntosh - waiting for a new workshop before I start the rebuild....

The cams are a little weird! Are they Stage 2 Yoshi's? If so, there shouldn't be any idler gear! Mine never had any (with Stage 2 cams), and did 10's of 1000's of km's - no probs. Well, no probs until the centers of the cam lobes started to disintegrate, due to the bozo's who originally fitted them not grinding down the little oil nipple on the underside of the rocker arms. Left little grooves in the middle of all the lobes - but still lasted a long time. I then switched the cams out, and put the ones in from the McIntosh (even more lift, and a LOT more duration than the Yoshi's) - still with no idler gear... and still no problems. The GSX used to get a good thrashing too - Vic club road races (err rides), track days, Carterton and Lyall Bay sprints (best SS1/4 11.1 sec, best flying 1/4 - 143mph, and still accelerating!).

My recommendation is to go into Wellington Motorcycles, and try and speak with Steve Dundon, as he was the GSX tuning guru for the time...

[Big T]

how does one post a photo?

You need a photo hosting site. Most people use Photobucket, since it's free.

Go to Photobucket.com and set up an account. Upload your photos into the account. Then, left click once on the IMG Code line below the photo. A small box saying "Copy" will pop up. Now, go to the GSR posting you're writing, right click and paste it into your post.

It will come out like this



I'd really like to see some photos of your bike. It will take you 15 minutes or so to set up your Photobucket and load up a few pics.