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hi i have a 83 vmax 540 and it wont go past 60mph reason im thinking is because there is a noise comeing from the drive shaft that spins the track or somewhere real close when i go full throttle and let off at anywhere around 45 to 60mph as in letting off the throttle completely it makes a wierd noise like a clunking noise every couple seconds for about 10 to 20 seconds and help would be greatly appreciated, on the other hand i love how quick and light this sled is im 18 and had a 91 indy 650 super fast but alot of problems a 95 vmax 600 ate gas and oil like it was going out of style and now the vmax 540 its mint and am going to keep it that way these old sleds have a lot of history with yamaha!! so please can someone help, thanks travis

Travis, Welcome to Vintagevmax ! I would remove the drive belt and spin the seconday over by hand to listen and feel for a rough bearing. I would first suspect the speedometer side drive axle bearing (below the secondary) and behind the plate with three bolts and the cable. Then, I would take a good look at the secondary side jackshaft bearing. Make sure you give the primary clutch a good cleaning and inspection !

hi i checked the chaincase side already because thats where i heard the noise coming from and that bearing is fine and now i will go out and check the other side and check the clutches and let you know here in a little while, thanks for your help it is greatly appreciated

one more question what would i look for in the primary clutch as in inspecting it for damge its a comet 108 and have heard a lot of bad things, so again any information would be great guys. thanks travis

the 108 isnt a bad cluth it just wasnt designed to be used with the 540's stock secondary... you want to be looking at the profile of the weights that is to make sure they are "smooth" with no flat spots... also make sure the rollers are smooth and not sloppy

ok i understand that so what secondary clutch it made to go with that clutch? i have a spare secondary from my 95 vmax 600 will that work?? let me know thanks for the advice

also 1 more think what kind of oil can you put in your chain case instead of buying the exspensive stuff?? is there any substitutions for it?

vmax540liq wrote:also 1 more think what kind of oil can you put in your chain case instead of buying the exspensive stuff?? is there any substitutions for it?

I have run Dextron automatic transmission fluid for years. It is lightweight, lubes well and doesn't gell !

thanks man that really helped me out!!! thanks travis

AND its red so if would happen to leak you know what kind of oil it is on the floor

yea that is very tru thanks to all you guys with information and ill let you know if i have anymore questions!! thanks travis

sorry to keep bothering you guys but another question is that i noticed that on the crankcase theres a dipstick and i read on here its to put oil in to keep everything in good working order could someone verify that for me and how much oil i have to put in it? thanks travis

i dont have the book in front of my but it isnt very much.... like 40cc or something... i believe the lines on the dipstick are there to hold the oil on it and NOT and indication of high and low...

ok thanks tyler i called a local powersports dealer and they told me 12ounces so i filled it up and its fine, also i checked both side bearings on the driveshaft and both look good and i put some grease on the side that the spedometer cable bolts up to and it seems to go a lot better not shure if its the fresh chaincase oil or grease on the one side of the drive shaft i also fixed a gas line that was sucking air that also could of been part of the problem. thanks for all the help guys!!!

vmax540liq wrote:ok thanks tyler i called a local powersports dealer and they told me 12ounces so i filled it up and its fine, also i checked both side bearings on the driveshaft and both look good and i put some grease on the side that the spedometer cable bolts up to and it seems to go a lot better not shure if its the fresh chaincase oil or grease on the one side of the drive shaft i also fixed a gas line that was sucking air that also could of been part of the problem. thanks for all the help guys!!!

Your dealer doesn't know what he is talking about. According to the service manual the water pump gearcase on a Vmax 540 engine holds 1.18 to 1.35 ounces and calls for SAE# 75 or 80 API GL-3 gear oil. I used Amsoil synthetic gear oil in mine. If you put 12 ounces in there you will have a mess if you run it. The only way to drain the oil is to remove the plug in the bottom of the case which requires unbolting and lifting the engine.

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