Camshaft Specs Anyone?

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Vmaxattacks

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Does anybody have or can link to the camshaft specs/valve timing specs? Is it true or is it not that the 49-state and the California engines have DIFFERENT camshaft lift/duration and centerline dimensions as well as valve timing specs?
Thanx,
Bud
 
One time I was going to help a guy replace california cams.We got in there and the cams had the exact numbers as the replacements so we left them in.You could look at the part numbers for each at www.yamahamotors.com this is where I get all my part numbers before ordering from U/Motors.I then go to bike bandit to get the full retail price(which my local shop charges)Then multiply it by .6 and get the U/Motors price.
 
I looked at the part numbers and they seem to be the same?I would bet John at PCW would know for sure.
 
They're the same. Here's an old snip from the Yahoo list.

Cams (1FK-12171-00-00/ 1FK-12181-00-00) for CA model '85 thru '88 Vmax are the same as 49 state model thru 2003. Near as I can determine, even tho the carburators have different part numbers, all jets and the needles for the '85-86 CA and 49 state (VMX12N/NC, VMX12S/SC) models are identical.

Mark
#1098
 
They're the same. Here's an old snip from the Yahoo list.

, all jets and the needles for the '85-86 CA and 49 state (VMX12N/NC, VMX12S/SC) models are identical.

Mark
#1098

Except that the Cal. carbs have a #100 PAJ-1
 
OMG, this is a VERRRRY old thread..... anyway I found this from the manual:

Throttle valve size​
#125 (USA, EUR), #130 (California)

 
That is the part number not the size. It's the number stamped into the butterfly. I think the difference is the size of the air bleed hole. Won't effect performance at anything except idle.
 
Sean, I am glad you showed up here in this old thread.
I just read the old story about the very first 1985 Maxes that they were stronger than the rest. Someone wrote on a youtube comment that they had 1.5 degree camshaft timing advance. I also seen some different part numbers on the fiche. In the Vmax history it was mentioned that in 1991 for Europe they had an increased valve duration and also changed the rear transmission ratio to improve acceleration. what is the true story? I am building a complete bike and I can mix and match 1986, 1997 and 2003 parts into the blender, advance the timing if needed, etc.. etc... to make the best Vmax-smoothie I can possibly afford despite of the global recession heavily impacted wallet.
 
Sean, I am glad you showed up here in this old thread.
I just read the old story about the very first 1985 Maxes that they were stronger than the rest. Someone wrote on a youtube comment that they had 1.5 degree camshaft timing advance. I also seen some different part numbers on the fiche. In the Vmax history it was mentioned that in 1991 for Europe they had an increased valve duration and also changed the rear transmission ratio to improve acceleration. what is the true story? I am building a complete bike and I can mix and match 1986, 1997 and 2003 parts into the blender, advance the timing if needed, etc.. etc... to make the best Vmax-smoothie I can possibly afford despite of the global recession heavily impacted wallet.

I can tell You for sure that final drive ratio was diffrent in the pumpkin.
Personaly checked that.

I've heard the stories about the cams but no one verified that yet.
 
Not sure what the ratio differences were and was not even aware there was any. I'll have to eventually check the engines I have and put the rumors to rest. We have not seen an appreciable difference between the 85 and the newer engines.

Sean
 
The final drive ratio is either 3.3 to 1 (Euro) or 3.66 to 1 depending on model.

I think I have that the right way round - the European version reduces the revs relative to the rod speed.
 
The Vmax diff is 3.66 here in the states (and everywhere that I knew of). The Venture diff upgrade (downgrade) is 3.33 and allows for less rpm's while cruising but hurts acceleration. I'd like to find a 4.11!

Sean
 
Hmmmm.... anyway, it is acceleration I am after, so the 3.66 is okay.
I agree, I would love a 4.11 ;)
Now the cam specs story, I guess Sean would be the Myth Buster in this area.

At that stage ( one motor dismantled, the other out of the frame ), I do not mind tweaking them and getting some extra power !!!
 
Not sure what the ratio differences were and was not even aware there was any. I'll have to eventually check the engines I have and put the rumors to rest. We have not seen an appreciable difference between the 85 and the newer engines.

Sean

In the 1990 Yamaha changed the final drive ratio form stock 33/9 3.66 to
33/10 3.3 in the european models (100,2 HP at 7500rpms).
The european model runs with limited diaphrams and no v-boost valves.
Also visible smaller mufflers outlets.

Not confirmed the changes in the cams.
However:

http://www.biker.net/vmax/vmax_history.htm

* Modifications to suit noise regulation from 83 to 81 dB. Exhaust system changed and max. power decreases from 100.2 HP/ 7,500 rpm to 95.2 HP/ 8,000 rpm.
* New camshafts with lengthen valve opening to improve character: Max torque of 10.3 mkg (74.5 ft-lb) is at 3,000 rpm only (formerly 10.9 mkg (78.8 ft-lb)/ 6,000 rpm). To keep superb acceleration, rear transmission ratio is changed from 33/9 to 33/10.
 
Satariel, you are right. I feel that with some correct mix and match we could get some free HP... maybe? I hope...
 
"For Europe:

Modifications to suit noise regulation from 83 to 81 dB. Exhaust system changed and max. power decreases from 100,2 HP/ 7500 rpm to 95,2 HP/ 8000 rpm.
New camshafts with lengthen valve opening to improve character: Max torque of 10,3 mkg is at 3000 rpm only ( formerly 10,9 mkg / 6000 rpm). To keep superb acceleration rear transmission, ratio is changed from 33/9 to 33/10. "
 
"For Europe:

Modifications to suit noise regulation from 83 to 81 dB. Exhaust system changed and max. power decreases from 100,2 HP/ 7500 rpm to 95,2 HP/ 8000 rpm.
New camshafts with lengthen valve opening to improve character: Max torque of 10,3 mkg is at 3000 rpm only ( formerly 10,9 mkg / 6000 rpm). To keep superb acceleration rear transmission, ratio is changed from 33/9 to 33/10. "

Is there something diffrent between this and what I posted?
 
Here are the camshaft specifications for 1986 - 2005 lift is .325 int .325 exh / duration at .050 is 236° duration at .040 is 240° make sure if you are using this for a comparison you check what they are measuring the duration at it seams no one uses the same thing.
 

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