Cam questions

[Guest]

I picked up my '82 1100e late in the season last year, and all I did was change the oil and ride it. Now that riding season is here, I'm doing the 'real' maintenance before I start riding on a daily basis.

I went to check the valve clearances, and ran into a slight problem. The service manual indicates that you use the notches on the end of the cams to determine the correct position for checking the valves, which makes sense, however when I went to do this, I found that there was a notch on the end of the intake cam, but none for the exhaust cam. I took a look at the left end of the cams, and found the exhaust cam had a notch over on that side. Any thoughts on that one?

I also noticed that the cam sprockets were slotted for degree-ing the cam and I don't think Suzuki made them that way, is this the work of a previous owner?

I did pull some info off the cams, both of them have YRD ST1 stamped into the cam near the sprocket. The intake sprocket has 451 on it, and the exhaust cam sprocket reads 470.

Any info or thoughts would be helpful.

At least the valve clearances were all good, and everything looked clean and well cared for under the valve cover.

[Steve]

Sounds like somebody put the exhaust cam in backwards.

Another clue to look for: the bolts that hold the sprocket to the cam should be on the same side for both cams, and they should be on the right side of center.

.

[kawfeedave]

I thought of that for a second, but I checked that the cam sprockets were both attached the same way and also realized that you cannot put the cam in backwards due to the tach drive. If you put the cam in the wrong way, the tach drive gear would be on wrong side, and mine was on the right side as it should be.

[tkent02]

I don't think they ever came with slotted sprockets, someone has been in there before you. Might be a reground or other aftermarket cam, measure it to see what you have.

[TheCafeKid]

YRD ST1 cams are Yosh cams...someone has been in there before and you just got a sweet bonus...

[kawfeedave]

YRD - Yoshimura R&D, I can't believe I didn't pick up on that. I found out that ST1 means Stage 1, as they still use that name today.

I'm not sure I'm going to pull them to measure, I just got the top-end buttoned up tonight. Anyone happen to know the specs on these?

[TheCafeKid]

YRD - Yoshimura R&D, I can't believe I didn't pick up on that. I found out that ST1 means Stage 1, as they still use that name today.

I'm not sure I'm going to pull them to measure, I just got the top-end buttoned up tonight. Anyone happen to know the specs on these?

Type ST-1
MAX LIFT(mm) IN 8.25mm/EX 8.25mm
1mm DURATION(°) IN 245°/EX 245°
Standard Tappet Clearance(mm) IN 0.15mm/EX 0.15mm

[TheCafeKid]

By the way these are still sold in Japan for the GSX1100S Kat. At least that's what this website says... I know it's for the Kat but they very very likely the same cams...

Also, I'd be curious to know what whomever set them at as far as degree.
They also have stage two available...
Are these still available here? Anyone know?

[tkent02]

You should at last measure the cam timing, very few PO's are competent enough to do this right.

[kawfeedave]

As always, this site delivers the info in no time flat. Thanks guys.