Cam Degreeing or not

[RustyTank]

Some degree wheels have their primary markings in a full 360 degree circle, some in two 180 degree halves, and some count up and back down every 90 degrees. If the blurry, yellowed, stained, brittle, seventh-generation photocopied instructions from the early '80s you are working from used one system and the degree wheel you happen to have on hand uses another, you will need to be comfortable "translating", or at least make sure you're consistently using the correct set of markings.

Is there a degree wheel type you suggest for easier reading?

It's also one of those times it's important to understand "why" you're doing something rather than just following the numbers in the instructions. No valves or camshafts were harmed that day, only our foreheads from the resounding double smack when the light finally dawned.

Great post BW. I'm finally starting to understand the why...I use the word "starting" loosely...at this point it's the terminology that's got me scratching my head. I'm having to learn a new language of sorts, all this talk of degree and timing. I'll get it, but I'm just not quite there yet.

[bwringer]

Is there a degree wheel type you suggest for easier reading?

No idea... they all will work just fine; you just have to understand what you're doing. Make sure the center hole size matches the bolt you're using, I guess (8mm, IIRC)? I'd likely lean toward a simpler one; some have all sorts of added markings on them. It's also important to make sure you're viewing the marks from a consistent, correct angle. If the bike is on the floor, you're going to have to get on the floor too.

In our case, the photos in the instructions were just vague blurs; 1980s photocopier technology was pretty primitive. So we couldn't tell what they were using and had to depend on the written instructions. Some numbers were also too blurry to read, so there was some detective work and deduction to perform.

[zed1015]

Just buy a Motion pro degree wheel or an APE one they are all the same thing.
Good quality etched aluminium, clear markings and cheap.
I've used the exact same one for 20 years or more.
Motion Pro 08-0092 Motion Pro Degree Wheel | eBay

[RustyTank]

Just buy a Motion pro degree wheel or an APE one they are all the same thing.
Good quality etched aluminium, clear markings and cheap.
I've used the exact same one for 20 years or more.
Motion Pro 08-0092 Motion Pro Degree Wheel | eBay

Perfect. Thanks zed. Lets just go part by part here, lol

What do you guys think of this Ape TDC indicator?

https://store.schnitzracing.com/ape-top-dead-center-indicator/?sku=TDC10&gclid=EAIaIQobChMIhuT15ZmZ7wIVIg_nCh2deAUhEAQYASABEgL_8vD_BwE

[zed1015]

Yes! just make sure you buy one with the correct size thread or as already suggested you can make your own from a stripped out spark plug.
If you do opt to make one just be sure the stopper is slim enough to miss the valves as they open and close.

[RustyTank]

Yes! just make sure you buy one with the correct size thread or as already suggested you can make your own from a stripped out spark plug.
If you do opt to make one just be sure the stopper is slim enough to miss the valves as they open and close.

I'd prefer to buy one. I think the 10mm version they sell will work but I'll double check.

[bwringer]

I'd prefer to buy one. I think the 10mm version they sell will work but I'll double check.

What bike? You'll need a stop with a 14mm thread for an 850G and most or all 8 valve GS models.

Most or all 16 valve GS models (like the 1150, 1100E, etc.) would need 12mm.

Not sure whether those are absolutes, so look up your spark plug specs.


As far as a degree wheel, the Motion Pro is simple and is marked in 90 degree quadrants. The Summit Racing version goes up to 180 and back down again. There's a comp cams version that has two different scales. Some of the ones intended for cars are awkwardly large. I'd go Motion Pro, personally. Pay attention to the diameter of the center hole, too -- many of the car versions have a larger hole and don't come with bushings to make sure they'll work on a bike.

If you're measuring lift, a dial indicator and base from Harbor Freight will be perfectly fine. Magnetic bases can be pretty awkward and move around since all you have nearby are round frame rails, so a clamping base with a piece of leather to protect the frame might be better. Get some good lighting, set up a pointer with a piece of wire, and develop your strategy for using a consistent point of view to read the runes...

If you do a Google Image Search for "degree wheel" you'll get an idea of the variants.

[mmattockx]

How does one go about finding the settings for what they want?

If you have aftermarket cams then ask the manufacturer first. If you are using stock cams, then GregT's numbers are a good place to start. I went to 106I/108E on my 1100E and it was a major improvement over the stock lobe centers. It gives up nothing down low, comes into the power smoother and earlier and revs hard all the way to redline. It is so much stronger than it was at the stock numbers that I started getting clutch slip around 7000rpm in the higher gears where I never had a problem before the change.


Mark

[RustyTank]

What bike? You'll need a stop with a 14mm thread for an 850G and most or all 8 valve GS models.

Yeah it's an 850. I honestly didn't know, was just guessing. Thanks for the info BW.

[RustyTank]

If you're measuring lift, a dial indicator and base from Harbor Freight will be perfectly fine. Magnetic bases can be pretty awkward and move around since all you have nearby are round frame rails, so a clamping base with a piece of leather to protect the frame might be better. Get some good lighting, set up a pointer with a piece of wire, and develop your strategy for using a consistent point of view to read the runes.

Are these the parts we're talkin about?

Dial indicator

https://www.harborfreight.com/1-in-travel-machinists-dial-indicator-63521.html

Indicator with mount and clamp. Looks to be the same dial indicator as above but I can't tell for sure.

https://www.harborfreight.com/clamping-dial-indicator-63656.html

[limeex2]

One could assume that differences in cam timing is one of the reasons 2 of the same model bikes are faster or slower than each other.

[zed1015]

One could assume that differences in cam timing is one of the reasons 2 of the same model bikes are faster or slower than each other.

Production tolerances can affect the performance slightly between machines coming off the production line but it would hardly be noticeable.
If one slipped through quality control with noticeably less power we'd call that a Friday afternoon or Monday morning job ..
After that wear and mileage etc would be more of a factor.
If you get a stock motor though and degree the cams in to spec it can sharpen the performance up a bit depending on can chain wear etc..

[gs11ezrydr]

One could assume that differences in cam timing is one of the reasons 2 of the same model bikes are faster or slower than each other.

I could agree. Back in the early 80's at one time we uncrated and assembled as many as seven 1100's in a day and there was a few that were faster and slower after break-in.A few customers complained about the issue..But cam timing if food for thought there..Along with clearances,tolerances,etc.

[metalfab]

There is a lot of good info on this thread. Here is my take on the subject. Cam timing is a lot like jetting. If it is close it works, but.... Having it down cold and near perfect makes a big difference in the way an engine runs. You can dial in top end power, or midrange power with the same setup. Advancing favors bottom end power, retard favors top end power. Changing cam timing from stock alters valve to piston clearance keep an eye on that. Any wear in the, chain, cams, sprockets, or chain guides can alter timing. Then add machining imperfections to the mix. It is only hard until you do it, when you learn how to do it opens a window, and you become a more professional better engine builder without a doubt. Learn how from tech support at cam manufacturers support websites.

[Big Jay]

Let me clear something up here...What Web means by "drop in" cams is they will work with stock valve springs and pistons. Non drop ins will require valve pocket machining or aftermarket pistons, and high performance springs.

Having said that, all cams should be agreed in to get your money's worth, Back in the day, there was a shop that discovered that stock GS1150 cam timing was all over the place. He would provide a "tune" for them which amounted to degreeing the stock cams in.