Degree the cams?

[Buffalo Bill]

To degree, or not to degree. That is the question.
Is a lowly street bike and daily rider worthy of such effort?
I understand that by degreeing the cams you're just moving the power band to another RPM range.
Valuable adjustment for a race bike, but should I bother to do it with my 1100G?
I was thinking it may be worth the learning experience, and probably interesting.

 

[Guest]

your thinking is correct, I think.....did it on my 1100 b/c of a cam swap. Learning experience for sure. Not that hard once you grok it, but it takes time to grok to fullness

 

[Buffalo Bill]

your thinking is correct, I think.....did it on my 1100 b/c of a cam swap. Learning experience for sure. Not that hard once you grok it, but it takes time to grok to fullness

I didn't know you did a cam swap, can't remember a post about it, but can't remember a lot of posts here.

 

[Guest]

just stock 1150 cams, not anything too exciting

 

[posplayr]

just stock 1150 cams, not anything too exciting

On the 16V bikes the Exhaust cam on the 750E and the 1100E is the same, so you can boost up the 750 intake side with the 80-82 1100E intake cams. On a bone stock 81 GS750EX I had a noticeable increase in pep and had to bump-up the main 1 step size.

If i was going to degree a cam, I would see if there are any step up cam option that would not break the bank.

 

[bwringer]

It does add a small potential failure point; there's some nonzero risk of the bolts backing out and letting the sprockets whack around, or the bolts getting loose and creating chaos.

What that degree of risk is, I dunno, but I've seen it happen (bolts didn't get loose, fortunately). However, in that case we had no idea who had originally done the modification, so perhaps it was just human error. We buttoned things up with new grade 12 bolts, proper torque, and red Loctite, and had no further issues.

I'm not sure if there are any cam options for an 1100G. You could start by using a stop, degree wheel, indicator, etc. to take some careful measurements of the stock cam setup.

I also learned the hard way during that project that there are different types of degree wheels (some are marked for 360 degrees and some 180 degrees and back to zero), and trying to follow instructions to the letter without being aware of the difference is one sure path to insanity.

 

[bitzz]

...
I understand that by degreeing the cams you're just moving the power band to another RPM range.
....

Degreeing the cam is checking the cams are opening/closing when you think they are. You would degree stock cams if you were blue printing a motor.
To change the "power band" you would move the "centers" or timing of the cams, by changing the clocking between the two cam and/or the crank.
Off the top of my head a stock GS wants the cam centers at 105 degrees, lots of overlap.
IIRC my GS is set at 110 degrees. Helps top end, kills gas mileage

 

[posplayr]

I got a lot of grief about this but it works very well and uses the small degree wheel.

https://www.thegsresources.com/_forum/showthread.php?139950-High-Accuracy-Degree-Wheel&highlight=high+performance+degree+wheel

 

[ArttuH]

Regarding question if it's worth of effort for stock(ish) street bike. Well, you never know... I would say that moving the cam timing from stock values to something else probably won't provide huge improvement. But there is one catch. At least my experience is that stock timing can be quite badly off from the spec from the factory. I have seen over 10 degree variations. So if you bike happens to be this kind worst case sample then you might get noticeable improvement just by degreeing the cams to the factory spec.

 

[Buffalo Bill]

I got a lot of grief about this but it works very well and uses the small degree wheel.

https://www.thegsresources.com/_forum/showthread.php?139950-High-Accuracy-Degree-Wheel&highlight=high+performance+degree+wheel

Thanks a bunch, interesting read for useful info. Also an interesting debate.

 

[Buffalo Bill]

Regarding question if it's worth of effort for stock(ish) street bike. Well, you never know... I would say that moving the cam timing from stock values to something else probably won't provide huge improvement. But there is one catch. At least my experience is that stock timing can be quite badly off from the spec from the factory. I have seen over 10 degree variations. So if you bike happens to be this kind worst case sample then you might get noticeable improvement just by degreeing the cams to the factory spec.

I think you're right, it would be useful to check my engine for accuracy.
I've been reluctant to spend money on rarely used tools, but a dial indicator can be used for other things too.
Learning a new skill has surprising usefulness in unrelated work.

 

[rphillips]

Changing the cam timing can make a very noticeable difference in the feel of the bike. I enjoy lower end torque much better than top end peak HP. For me, it was a little aggravating to get things set up, the first time, Something in the cyl. to measure find TDC, a good solid mount for the dial indicator, good solid pointer for the degree wheel. But after you do it & see what is involved, back in the day it was well worth the effort. Now days, I just ride them like they are. Just not as energetic as I once was. But yeah, I would recommend it. Just my opinion.

 

[Guest]

I picked up a good enough dial indicator at harbor fright for low $$. Also, I just forwarded an old article to ya, to the email in your profile....

 

[Buffalo Bill]

I think those frustrating bikes that just don't respond to carb tuning, could be poor cam timing. Another possibility to eliminate in any case.

 

[Spyder]

On the 16V bikes the Exhaust cam on the 750E and the 1100E is the same, so you can boost up the 750 intake side with the 80-82 1100E intake cams. On a bone stock 81 GS750EX I had a noticeable increase in pep and had to bump-up the main 1 step size.

If i was going to degree a cam, I would see if there are any step up cam option that would not break the bank.

I have an '83 750 engine. Can I put the intake cam from an '80 1100 ? I have a blown up '80 1100 engine, and the original '83 750 needs a valve job. Would be a great time to change out the cam.

 

[wyly]

To degree, or not to degree. That is the question.
Is a lowly street bike and daily rider worthy of such effort?
I understand that by degreeing the cams you're just moving the power band to another RPM range.
Valuable adjustment for a race bike, but should I bother to do it with my 1100G?
I was thinking it may be worth the learning experience, and probably interesting.

My mechanic(ex racer, SBK crew chief) whose bike knowledge is on another level tells me to degree my cams for midrange. He's going give me more midrange because that's where I ride/live 99.9% of the time. The vast majority of riders rarely visit the upper end of our bikes range unless they're a track day enthusiast.

 

[posplayr]

I have an '83 750 engine. Can I put the intake cam from an '80 1100 ? I have a blown up '80 1100 engine, and the original '83 750 needs a valve job. Would be a great time to change out the cam.

I was thinking 890-82 GS750E and 80-83 GS1100E. I'm not that familiar with the 83-85 750E. That engine is a morf toward the gixxer motors. I would not completely rule it out but i would say not probable. I know RapidRay has purt some Gixxer cams in the early 16V 1100 heads although there are journal mismatches.

 

[Tom R]

I think you're right, it would be useful to check my engine for accuracy.
I've been reluctant to spend money on rarely used tools, but a dial indicator can be used for other things too.
Learning a new skill has surprising usefulness in unrelated work.

Pick up a set of v-blocks while your at it. You’d be surprised how often you actually use them.

 

[Guest]

To degree, or not to degree. That is the question.
Is a lowly street bike and daily rider worthy of such effort?

In my experience, it absolutely is. The first time I did it on my 82 (in early 2005) I simply put them accurately to the stock numbers from the manual. I then revisited it in 2017 and put the lobe centers to 106I/108E. It significantly changed the way the bike ran, with power starting lower in the RPM range, a smoother transition into the power, very noticeably stronger mid range and no loss of top end that I can tell. It is enough stronger that I now occasionally get clutch slip around 7000rpm in the higher gears and I never experienced that with the stock cam lobe centers.

It may be worth noting that my bike also has APE pod filters and a Kerker 4-1 canister exhaust system on it, so I can't say that a completely stock bike will respond as mine did. Nothing else was changed when I did the cam timing and the bike was well setup and tuned for the pods and pipe before the timing change so it was all due to the change in lobe centers.


Mark

 

[Buffalo Bill]

I'm thinking the sprocket bolt holes need to be slotted to adjust the cam timing, right?