FZ6 Cam Install Project


Scott_Thomas

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Elite Member

DainiusD

New Member
OK, wider chain makes sense now...
Is there a link or at least any pics of that cam degree thing?? I still don't get it, I thought cams have fixed position with gears...
 

Scott_Thomas

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Elite Member
OK, wider chain makes sense now...
Is there a link or at least any pics of that cam degree thing?? I still don't get it, I thought cams have fixed position with gears...
Take a peak at this... I4 DOHC from a cage - notice the slotted cam gears? Apply this same concept here but in this case, you or the machine shop slots the existing holes to obtain the LC desired. By slotting the existing holes it allows you to change the lobe center in relation to crankshaft / piston position. This changes the torque curve of the engine.
The amount you slot the gears is based om degrees of rotation od the cams bolt circle radius.

How to degree your DOHC engine

The link explains the math, logic, and has pictures.... take a peak.

Also as written throughout this thread, getting a dial indicator around the cams and squarly onto the valve spring retainer is a serious PITA. You need a dial indicator with a screw in tip that you can molest one of the tips by welding a sturdy wire to it and form that around the cam lobe touching the spring retainer...

Here I'm checking TDC after advancing the ignition timing on the FZ6...
 
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Scott_Thomas

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Elite Member

Marthy

World Most Bad A$$ 6R
Elite Member
Exhaust cam should be very close but the intake cam need to be advance 3 degree if I remember well. 0.008" slot per degree... remember 2:1 ratio! 1 degree at the cam is 2 degree at the crank.

ILC 102 degree
ELC 104 degree

Under 4K rpm the bike pull as strong as a 20yo mopped. LOL But it comes alive pass 4K with a greatly improve mid range over stock. Peak HP should be around 10250rpm and it pull strong all the way to 12K. It's kind of a b%$% to get it right but all you need is patience. Hitting those numbers are important... 1 degree make the whole difference. If you have an exhaust with that, get a good custom tune. Well worth the investment.
Are both the FZ and the R 105/105 stock? Its been too long.
 

DainiusD

New Member
Thank you guys, all clear now. I think I'll risk doing it. It's just a matter of getting parts and bike off the road, what is not much possible on these sunny spring days :)
 

gbisch

New Member
This is an old thread, but maybe someone will see this :)

What is the reliability of the bike doing this cam swap? Anyone ran into any major problems a few thousand miles down the road? I just ordered FZ6 cams and FZ6R cam gears off Ebay. I'm going to do a host of other mods where i'll be tearing into the engine so I figured I would do this as well while i'm in there.

I saw another post talking about swapping to R6 exhaust valve springs. Has anyone ran into issues using stock valve springs? I'll stay stock unless there have been issues with stock.

Can you run the FZ6 cams AND the 4 degree Advanced Timing gear? Or is that a recipe for disaster?

Does anyone have a good PCV map for the FZ6 cam swap?

And what front and rear sprockets did you run with this setup? Would you have a hard time keeping the front wheel down with -1/+2?
 
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Marthy

World Most Bad A$$ 6R
Elite Member

gbisch

New Member
Never had any issues with that setup. Yes, 4 deg timing work fine.

Exhaust cam goes on the original timing mark on the gear. Leave the valve lash on the loose side of the specs.
Intake cams need to be advance few degrees. I had it to 102 degree (3 deg adv) it was awesome but not much was going on before 4K RPM. This time I went a little more advance (slotted 0.038" and sent it LOL)

I have a map done but not with an exhaust. I kept the stock exhaust with twin outlet. Might get you in the ball park?
I’d sure take the map if you would email it to me. I’ll PM you my email.
 

Rumpig

Member
I've done around 40 000km running standard valve springs with FZ cams , all without a problem. You only need to upgrade the springs if raising the rpm limit.
Best mod along with the timing.
 

audace

New Member
I hate to bump an old thread, but I had a couple questions regarding the timing adjustment and machining on the cam gears. Hopefully Marthy happens to see this.

What's the particular reasoning for the slotting of the cam gear to advance the timing? Does the slotting make up the difference between a non-slotted FZ6R gear and the original FZ6 gear?

Interested because I'm trying to start collecting parts for the winter and have another idea.
 

Rumpig

Member
You can get away with not slotting the gears but there will be a bit of a flat spot down low . The timing Marthy quotes works the best . Pulls from 4000 rpm to redline .
 

audace

New Member
Makes sense.

I just found a nice deal on a matched FZ6 cam/crank set and I saw that Yamaha has a really easy system for picking out main and rod bearings. Since I'll have the motor out and the bottom open this winter, I was curious as to whether or not keeping the FZ6 cam gears and popping in an FZ6 crank would achieve more or less the same thing.
 
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