Degree the cams?

[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.

[mmattockx]

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?

[storm 64]

Yes, the sprockets need to be slotted. I could do that for you... I have some 1100 4 valve sprockets. I'm not sure if they are same as the 1000/1100 2 valve sprockets. I suppose you could send me your sprockets and I'd slot them and send them back to you.

Some people would use a Dremel tool to slot them. I can do a more professional job of slotting them.

[Buffalo Bill]

Thanks Norm, I've been thinking about how to do it. I'm sure I'll enjoy slotting those myself. I was thinking a drill press would work if done slowly.
If it only needs a few degrees of adjustment, that would be a very short slot.

[Tom R]

Slotting them yourself is not a terribly difficult job. Degree your cams before you remove them to figure out which way you want to go. I have ‘83 cams in my 1100 that were 107.5 / 98 ex/in center lines. I left the exhaust cam alone, slotted only the intake sprocket and degreed (is that a word?) it to 105. Really changed the feeling of the bike... it used to start to lift the front wheel around 6000 rpms.....the front end still starts to feel light at that point, but it doesn’t really lift the wheel anymore; but it feels much quicker 6500 to 9000. I like it, though in reality I don’t redline it all that often. But it’s nice to have.
I just figured how far 8 degrees should be, marked it out on the sprocket, and filed it by hand. I was attempting 106, but I figured close enough for my likes and not worth taking apart to file the sprocket for another degree.

[Dalfort]

To be honest I would not bother on a bone stock bike unless you just want to learn how to do it.

I played with cam timing a bit on my 16v 750E back in the late 80's. Its a pretty simple procedure but you do need a good dial indicator that holds true and a quality wheel and pointer setup. I made a piston stop out of an old sparkplug to find TDC.

It seems like all the performance cams back then specified 110 degree centers. I ran several Cam Motion regrinds over the course of several rebuilds and they were all 110 degree centers. Even the nice .350 lift MegaCycle street/strip cams, I probably have an old catalog with all the specs laying around somewhere.

I remember dialing the intake back into the 104-106 degree range to bring the power on lower in the rpm range but you gotta be careful as you can start running into valve to piston clearance issues.

I ran GSXR750 cams in a Bandit 1200 set up like that and with a set of RS36 Mikuni's it was an absolute beast in the midrange.

[Buffalo Bill]

I had a difficult time with the set screw in the timing rotor. Stopped when It looked like I was gonna round off the bolt head of the rotor.
Anybody have a trick way to attach the degree wheel without undoing the set screw?

[mmattockx]

I ran GSXR750 cams in a Bandit 1200 set up like that and with a set of RS36 Mikuni's it was an absolute beast in the midrange.

When you say "set up like that" do you mean the intake cam at 104-106 with the exhaust at 110 or something else?

I had a difficult time with the set screw in the timing rotor. Stopped when It looked like I was gonna round off the bolt head of the rotor.
Anybody have a trick way to attach the degree wheel without undoing the set screw?

On my 1100E I just unscrew the smaller bolt in the center of the large bolt on the end of the crank. No set screw in sight. Sounds like yours is different than that?


Mark

[Big Jay]

Back in the 80s when these bikes were new, there was one shop that did a tuneup that really woke them up. Whet he was doing was degreeing the cams. The stockers were all over the map. He did a lot of them, we supplied the sprockets.

[bobgroger]

I am wondering if any of you tack weld the sprocket to the cam once you are done degreeing? I have heard of a couple people that do, just wondering if it is common or necessary. If you do, do you remove the cams to do it or weld it in place trying to keep spatter out of the motor?

[Big Jay]

Not common. On Hayabusas they will tack weld the adaptor to the cam.

[GregT]

As Jay says, only if you've fitted an adaptor. I've never had a slotted sprocket move in use.

There are engines on which you couldn't weld the sprocket as they've got to come off to remove the cam. Honda SOHC comes to mind.
On those it helps to have an engraving tool handy to mark the sprocket position once dialled.

Jay's comment about the shop offering tuneups in the 80's rang a bell with me. I must have done 15-20 16V engines in a 3 year period. All dialled to 106/108
Happy days indeed, lol