cam advice

otakar wrote:

I think this poor guy is already confused. i believe he has a stock motor and almost sure he has a stock head. .365 #118 cam is a DROP in cam. I know for a fact that a 78 KZ1000 head will accept a .380 lift with a stock base circle as a drop in. But since the .365 is available off the shelf than I will stick with that advice. Web #118

That's a good grind for the bike Otto. Never said it wasn't. I pointed out a problem I had with a set.

What I sad is don't trust anything about drop in cams to be bolt in and go.

2 more examples

About a month ago I got a set of aftermarket cams and the thrust journals were .060" too wide :ohmy: I couldn't even get the cam cap on. The cam was replaced "no charge".

Had another set where they've now beefed up the sprocket boss area. The intake cam rubbed the head inside the cam chain tunnel on the #2 cyinder side. I had to grind them down about .050" to get them to work. The exhaust cam did not hit.

Both problems were from 2 different cam grinders :S

I recentlly had a J head in that was cast with tappet bore clearance chamfers on all the tappet bores. You could clearly see it was cast that way. Only one like it I've ever seen.

Some castings have wicked high casting ribs running up through the sweep area above the tappet bore. Other's have very little. Sometimes they come through without any.

I have a head right now that the combustion chamber has a big time flaw in it. A big blob of aluminum that looks like someone took a nail and pushed it down into the metal while it was still soft and pushed a chunk toward the intake valve seat. I'll get a photo.

It's not from an explosion in the motor. It's the casting.

I have a question related to this, maybe its a hijack but I don't care. When Ma Kaw put cams in a bike, were they degreed? I ask because I have GPz750 cams I'm putting in my 650, and I don't want to shell out for adjustable sprockets. How close will they likely be? Or is there no way of knowing unless I set up a degree wheel and check them?

T_Dub wrote:

I have a question related to this, maybe its a hijack but I don't care. When Ma Kaw put cams in a bike, were they degreed? I ask because I have GPz750 cams I'm putting in my 650, and I don't want to shell out for adjustable sprockets. How close will they likely be? Or is there no way of knowing unless I set up a degree wheel and check them?

From the factory, NO, they're not degreed.

Could you bolt them in and have them work? Yes, they'll probably be OK. BUT.....there's always that "BUT"

Buy the sprockets Tyler or slot yours. You've come too far to skip that step bud

Gman wrote:

Larry, where is a good source to buy the Cam Motion cams?

My question is, why insist on Cam-Motion? just curious, since there are so many other good cams out there.

Ok, ok, I've been told.

Any idea where I could get adjustable sprockets for a 650?

Make them out of your old sprockets like we used to do in the old days. It will take you about 20 minutes. You don't need much movement. If you grind 3/32 in both directions, that will give you more than enough.

I need to say this so the guy asking the original question understands.

It's not that the aftermarket parts world is full of junk or anything like that. However, as in all things produced in this world today, quality doesn't seem to be "Job 1" anymore.

It's not just me either. I talk to guys with performance shops on the phone all the time. We'll ring each other up when we come across the latest "gotchya".

Fortunately or unfortunately, depending on your point of view, these anomolies that happen with camshafts are not limited to any single cam grinder. I've seen issues with every brand of aftermarket cam I've used over the years.

If you build motors all the time, you just get used to seeing strange things that are not supposed to happen..but do.

If you're working on your first KZ motor and putting in aftermarket cams and cam related components, then you could get bit if you're not previously advised about things that really do happen.

I've done a lot of these motors. So has Jay, Plummen, Timebomb, Otakar, etc.

Sometimes we debate each other over personal preferences. That's just guys being guys.

In general, if you stay in that .365" lift range with aftermarket cams, you're going to be OK. But you still need to slowly turn the motor over with no sparks plugs in it and feel for any binding situations.

Look at the cam sprocket area to see if anything is touching the head. Look at each individual tappet bore to see that the lobe isn't rubbing anywhere.

If you run into something, stop. Determine if you can fix it yourself. The cam sprocket boss would be something you could fix.

A lobe rubbing the tappet bore is probably NOT somethng you'll want to attempt if it's supposed to be a drop in cam.

The first thing a cam grinder will do is haul out their disclaimer paper that ships with the cams and hold it up like a cross in front of a vampire.

The next thing they do is cry "coil bind".

None of that does the guy with the screwed up cams one bit of good. Especially if he's put them in the motor, fired it up and the head gets chewed up :dry:

See this cam. Drop in Grind. Drop in it, grind up the head :laugh:

'nuff said....you're fully informed on what to look for

Degree, what's that :laugh: I have adjustable sprockets on my GPz1150 and eyeball calibrated the cams. It runs like a raped ape. Can I make it better? Maybe if I was Drag Racing and I wanted to pick up that extra 1 to 2 Tenths I would. On the street who cares and no one can tell. Unless you are a PRO and your reactions are consistent to that point, YOU will never be able to tell the difference.

Yeah I think I'll do it anyhow. I have access to a machine shop so I'll slot the holes a few degrees on the rotary table on the mill.

Sorry for the hijack, but Larry has it covered haha.

otakar wrote:

Gman wrote:

Larry, where is a good source to buy the Cam Motion cams?

My question is, why insist on Cam-Motion? just curious, since there are so many other good cams out there.

Who's insisting?

Why are you trying to pick my posts apart?

Is it because I corrected you on the GPz cams in a KZ motor or is it just because you want to battle with someone?

If the latter, pick someone else...I have to get to the shop now

Larry C

No, just naive curiosity. The question was not directed at your post it was a question to query the other question. The reason I asked is because Cam Motion is just a "Blast from the Past", and the relative price difference between their cams and all the others on the market. Just posted as an innocent question. You know I would never argue with the Guru, The "Iyetola of max Air Floa" :laugh:

thanks for all the insight.It sounds like the most affordable upgrade would be the gpz1100 (83-85) cams,slot my stock sprockets and check everything for fit.That would mean electronic tach as well correct..I just torqued down the head last night, I may have to wait on the cam selection until money permits but at least I know what to look out for now. cheers.