vmax 600

D

denn69

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Anyone know the differences between the 94,95,96 v max 600 motors. I was told that they differed in hp. Any reason why?

Thanks Dennis
 

The 96 came with a thicker head gasket, reducing the compression ratio. I think the secondary clutch changed in 95, resulting in different clutching.
 
justheman80 said:
The 96 came with a thicker head gasket, reducing the compression ratio. I think the secondary clutch changed in 95, resulting in different clutching.
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True, and my 96 XT came with the GYT pipe as original equipment and I am not sure of the other models ? Any will take the earlier 94-95 thin head gasket just, make sure of your jetting and use good fuel.
 
1994 - 1995 were basically identical ( except for the new secondary clutch in 95') Good low end~mid range power...ok on the top end (average compaired to the competitors ) I think they were rated at @ 94-96hp if my memory serves me right.
1996biggest visual change - new exhaust pipe ( similar if not identical to the GYT kit single pipe kit for the 94-95vmax600). Also changed was a thicker head gasket and i want to say they might have been ported a tad different (Jetting & clutching was way different) Took away some of the snappy low end power and tried to give the sled more top end power. Made the stock clutching seem a little less resposive on the low end - but top end power was improved by 3% (or was it 6%) can't remember exactly. I think they were closer to 98-99hp. Yamaha had a TSB if you wanted a little more performance out of your "stock" 1996 600cc vmax by installing a thin head gasket "kit" along with thier recomended jetting & clutching.
Head gasket thickness by year
1994-95' .6mm
1996 1.4mm
1995-96 Mountain max 600's were .8mm
 
From my personal experience:
I had a 95' vmax 600 i bought new....good running sled stock..had the yami shop add the shims to the needle to lean up the mid range a bit, other than that-100% stock. went head to head with the XCR's,ZR's ..the Formula Z's were pretty damn fast for a 583....then my buddy bought a 96' vamx 600 XT brand new the next year...rode it for the first time and my 95' seemed way better / faster (except for the rear suspension-lol).....it's just his 96 lacked the snap down low...it was still a little better top end wise. Then I talked him into the thin head gasket kit and a maxximum clutch kit - that really woke up his 96' 600 XT - it was a frikken ROCKET after that. I swear to god i talked to Gary at maxximum performace three different times on what to do about trying to get the RPM's down - i added heavier rivets to the weights everytime, but it still liked climbing up past 8500rpm...sometimes @8800...and it still made good power and he put like 4000miles on it with no issues - heck, I bought a set of GYT twin pipes for my 95' because his was way faster than my still stock 95'.....I still couldn't beat him!!?? (with the yamaha recomended jetting that is) it wasn't until I talked to bender to safely down jet my carbs that i could eventualy walk him on the top end with the twin pipes.....that 96' of my buddy's was a freak of Machine!!!!! ahh the memories :2strokes:
 
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I dont mean to hi jack, but I just picked up an 88 Exciter with a Vmax 600 motor in it. To my surprise, it seems to have a mild port job and Im guessing by the looks of it the head was milled. It has a serial number prefix of 8CA. I was wondering if any of you guys could tell me the year of this engine.
 
Throttle Junkie35 said:
I dont mean to hi jack, but I just picked up an 88 Exciter with a Vmax 600 motor in it. To my surprise, it seems to have a mild port job and Im guessing by the looks of it the head was milled. It has a serial number prefix of 8CA. I was wondering if any of you guys could tell me the year of this engine.
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8ca is a 94 to 96 motor ..8CR is the 97-99 motor .....the 600 motors where identical port wise ........just head gaskets in 96 and of course the exhaust ...in 97 they went to triple exhaust ports while the 2nd gen cylinders fit the 94-96 bottom end IMHO the 1st gen cylinders are better due to the intake side ...........

Shawn remember I have one set up like that with the Aaen motor in it
 
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Yamaha Nutz said:
8ca is a 94 to 96 motor ..8CR is the 97-99 motor .....the 600 motors where identical port wise ........just head gaskets in 96 and of course the exhaust ...in 97 they went to triple exhaust ports while the 2nd gen cylinders fit the 94-96 bottom end IMHO the 1st gen cylinders are better due to the intake side ...........

Shawn remember I have one set up like that with the Aaen motor in it
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I do remember you saying something like that. Since the chassis that the 600 came in is pretty much junk, Im thinking about dumping it into a 540 chassis. When are you tearing your aaen motor down so I can copy the porting?? ;)!
 
As long as we are on the subject, is there any gains to be had doing a Phazer SX cut on the piston skirt or something similar to these 600's??
 
Shawn while yes and not on the intake cut .......mine has updated pistons (forged 8CR Yamaha pistons) .....sorry motor is all fresh and sitting on the shelf ......unless I make it safe for premium fuel with a different head gasket it will stay together .....still trying to decide what to do ......as far as putting in a 540 chassis ........that would take a lot of fab work
 
Aww c'mon Nutz!! Dont tell me your chicken to tear a fresh motor apart! LOL. So what is the difference between the 8CA and 8CR pistons?? I agree it would probably be a bit of fab work to dump the 600 in to the 540 but I see what needed to be done the 92 Exciter I have with the Cat 700 in it so I think it is doable with some time and a welder. Looks like mainly the front engine mount and pipes are going to be the biggest issue.
 
8CA pistons are cast ...and 8CR pistons are forged .....boost ports are different too ...and mine are way different ........yes anything is doable and pipes can be reworked to fit ...........definitely a improvement for the vmax
 
Hey Nutz, I noticed the 8CR pistons have the intake cut away where the 8CA pistons dont. I also noticed the the 8CR cylinders have a triple exhaust port. Do you know what the difference in HP is between the two motors?? My buddy had a 98 vmax and was pretty torquey on the low end but my slightly modded Exciter would smoke it. Just thought I would pick your brain.
Edit: I just re-read the thread. 95ish hp 94-96 and 98ish hp 97 and up.
 
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as far as the second gen 600 twin ....no way 98 ....the triple yes but not the twin IMHO the 97-99 600 twin was a turd ....yes triple exhaust ports like I sated earlier ....if you switched out the head gasket on the 2nd gen twin it make a big difference yes bot pistons have the same style intake cuts ....boost port holes are different ..smaller on the 8CR pistons
 
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