Looking for advice

Tyler

Tyler

New member
First off I would like to say hello to vmax4.com. I just got my first vmax 4 and I want to make it a rocket. It is a 1995 800 st with M-10 and 1.5 lug track otherwise all stock. 23/37 gears did a compression test and it was around 105 psi on all 4. I want to start with clutching I’ve read some post that mention "Tony's setup" and it sounds like people really like it? I would consider pipes and jets as long as it won’t hinder reliability. So please post your ideas and advice.

Thank you

Tyler
 

that M-10 and 1.5 track is going to cost you some speed...

now 105lbs compression, is defiantly low..but i`ll bet you got that using a cheaper comp gauge, and one with about a ft or so long hose, did`nt ya?

reason i say that, is because the cheaper gauges, especially the ones with somewhat long hoses always seam to read low..
when i first got my vmax 4 back together, that`s about what i got..was starting to panick, until i barrowed a friends snap on gauge and found closer to 130 across the board..

anyway, being their all even..that`s probley a good sign, that it`s a gauge issue (or method issue?), did you have the throttle wide open? was the motor warmed up or cold?
 
Welcome to the site! :schild27::schild27::schild27:

"Tony's setup" is used by many of the members here with excellent results. We know Tony as YAMMIEGOD3:16 and he has been setting up Yamaha sleds for racing for many years. You will find him on many sled sites on the 'net. A few of his setups are on the tech pages here: http://www.vmax4.com/vbulletin/blog.php?do=list&blogcategoryid=5&page=3 If you have any other questions about it, post them on the site or PM him. He has always been very unselfish in sharing his clutching secrets.

Shark
 
Comp testing

Al P,
That being said what is the prefered method for taking Compresion tests??
I got 108-110 across all four on a 92 i jst picked up, but that was with a foot long hose on the tester, cold engine and NO throttle.
Jst for a comparison I tested 1 cylinder on my other 92, my 95 and my 97 and they all read the same,
110 lbs, but it was under the same conditions.(12" hose, cold, no throttle)
Any advice will be greatly appreciated.
Thank you,
Bubba
 
I tested with 12" hose, cold, no throttle, well cold as in room temp (around 45 f).
 
Try it with the motor fully warmed up..and the throttle Wide open..(remove all the plug wires from the plugs, so it does`nt start on the other three that your not testing yet)...

even using the above method, fully warm motor, and throttle wide open..i found my vmax 4 freshly rebuilt to still have "low" compression until i barrowed a friends snap on gauge..

i have picked up another gauge, which still is`nt a snap on, that does read closer to the real number, but still not as high as the snap on...aparently, some of the lessor expensive testors, have softer hose`s that will expand and effectively soak up some of the preasure...and to add to the effect, they don`t have the shrader valve at the far end of the hose (near the head, but rather at the gauge)..so that just adds to the expanding hose issue..

anyway, what I look for now with my newer testor, that i know still reads a bit low, is evenness..if they all read VERY close to each other, I call it good..cause i don`t feel it`s likely at all, that all 4 cylinders, are going to have a problem resulting in almost the exact same low reading..

AL
 
Last edited:
Does it make a difference if the other 3 plugs are in the other cylinders while testing??

I had all 4 out...

Jst called Snappy, new tester will be here tomorrow.... :)

Thank you!!
 
Actually that`s debatable really..I`ve heard arguments either way...plugs in, plugs out...has to do with the lower end of the motor, and weather the cylinders are allowing air/preasure to move from one side of the base/crank area, or not..and/or how much..

personally I pull them all out, as I can get the motor to spin faster...(but i have also done it with the plugs in..I don`t remember seeing a difference..that I recall?)

the way I see it, once that piston is above all the ports..anything well below it, is now irrelevant...(but there`s where the debate can come in...did some of the air/fuel preasure seep past the lower crank and into the cylinder next door and up past the piston next door, via it`s cylinder ports?, effectively, costing some volume that may have added to the number?..or is that a mute point/thought?)..LOL
 
Last edited:
Yes, understandable... but in the long run what is a few PSI between friends?? LOL!!

ok, I've got to ask, what is the mice eating your vmax about???
 
jst4fun said:
Yes, understandable... but in the long run what is a few PSI between friends?? LOL!!

ok, I've got to ask, what is the mice eating your vmax about???
Click to expand...

hahahahaha...LOL..yeah really..LOL

Mice you say??....well...the little BASTARDS ATE my dash filters...pretty much all of them, including the area around the screens on the 95 and up models..then they left "leavings" all over in my air boxes....they basically turned my 95 into a hotel!!..

then..I picked up a 96, in which they ate comepltly through the main wire harness under the front of the dash at the front/base of the steering shaft area...must be about 25 wires there....all but about 4 comepletly chewed through..LOL

Anyway, I finally had it, so I hired on a couple thugs to keep a watchfull eye on my vmax 4...no mice has been seen since!!..LOL
http://www.vmax4.com/vbulletin/showthread.php?8549-Bring-it-on-MICE!!!&highlight=mice
 
jst4fun said:
Yes, understandable... but in the long run what is a few PSI between friends?? LOL!!

ok, I've got to ask, what is the mice eating your vmax about???
Click to expand...


HAHAHAHAHAHAHA!!!! LOLOLOLOL! ROFLMAO!!!!!

Al, I don't care who you are, that's funny right there!
 
Dude, you must have been sooo pissed!!!
I'm sorry to hear about your bad mouse-fortune and i will definetly keep it in mind when i pack mine away for the summer!!!
I'm thinking i am going to invest in an electronic ultrasonic rodent repeller.....

Thanks for sharing!!!
 
jst4fun said:
Dude, you must have been sooo pissed!!!
I'm sorry to hear about your bad mouse-fortune and i will definetly keep it in mind when i pack mine away for the summer!!!
I'm thinking i am going to invest in an electronic ultrasonic rodent repeller.....

Thanks for sharing!!!
Click to expand...

Good 'Ol Bounce dryer sheets work every time don't know why but they do put 8-10 around the sled and one in the muffler outlet and ur good to go. Has to be the bounce originals!!!
 
Hose length on a compression tester is irrelivant as long as the check valve on the tester is at the end of the hose and attatched to the head. The longer the hose the more pulls it may take for that cylinder to pump it's max PSI but as long as the check valve is doing it's job and holding the compression in the gauge length is not a factor. What is a factor is a tester that doesn't simulate the actual plug length or "reach" If you have a hold in rubber tipped type tester you will get lower readings than a screw in type. If the engine your testing uses long reach plugs and you have a short reach screw in tester it will read lower than what is actual. Quality of the gauge is also a large factor. In most cases what is most important is a PSI # that is within margines and equality between the cylinders. If you have that you are more than likely OK.

opsled

PS, I have a very good quality Sun screw in comp tester but I don't have a long reach end for it. A good friend has a very good Snap-On tester with a long reach end. We've tested them on different sleds to see if there is a variance. On a 750 his will read 10lbs higher than mine every time. On a Vmax-540 the difference is about 7lbs which only stands to reason. The larger the volume of a given cylinder is the less (percentage wise) the volume of "reach" difference will mean to that total volume.
 
opsled said:
Hose length on a compression tester is irrelivant as long as the check valve on the tester is at the end of the hose and attatched to the head. The longer the hose the more pulls it may take for that cylinder to pump it's max PSI but as long as the check valve is doing it's job and holding the compression in the gauge length is not a factor. What is a factor is a tester that doesn't simulate the actual plug length or "reach" If you have a hold in rubber tipped type tester you will get lower readings than a screw in type. If the engine your testing uses long reach plugs and you have a short reach screw in tester it will read lower than what is actual. Quality of the gauge is also a large factor. In most cases what is most important is a PSI # that is within margines and equality between the cylinders. If you have that you are more than likely OK.

opsled

PS, I have a very good quality Sun screw in comp tester but I don't have a long reach end for it. A good friend has a very good Snap-On tester with a long reach end. We've tested them on different sleds to see if there is a variance. On a 750 his will read 10lbs higher than mine every time. On a Vmax-540 the difference is about 7lbs which only stands to reason. The larger the volume of a given cylinder is the less (percentage wise) the volume of "reach" difference will mean to that total volume.
Click to expand...

that`s what I was reffering to when I mentioned the shrader valve being in the end of the hose, VS at the actuall gauge it`s self..

if it`s at the end of the hose, the hose will only expand so much, before it will then start pumping up the gauge to read the correct preasue..VS, if the shrader valve is at the gauge, the hose will be like a elastic expanding area (volume) that will basically push back after the piston reaches TDC etc...(hope that explination/description made sence..LOL)..
 
Vmaxmike said:
Good 'Ol Bounce dryer sheets work every time don't know why but they do put 8-10 around the sled and one in the muffler outlet and ur good to go. Has to be the bounce originals!!!
Click to expand...

+1....I`ve talked to a few people about that, and they swear mice won`t get anywhere near bounce dryer sheets...
 
You must log in or register to reply here.


Back
Top