Big Bore ?

YA*AM*A*HEAD

YA*AM*A*HEAD

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hey guys just picked up another 98 srx 600 ...was told it has a big bore kit by hauck ...with slp pipes ,delta 3 reeds ..but the clutch has exploded at one time ..so they took the primary and secondary off what i was told was 99 vmax 600 ...twin? i seen the sled but didnt think there was a 600 twin in 99 thought they was all tripples plus it was a canidian sled 200 kph speedo ...i am sure that robbed alot of power by doing this ..so i am waiting to see if he can get the helix and springs from the bad clutch and primary ........but what i need to know is how to tell if it is a big bore ? jugs still look stock with stock markings ...and the guy was unsure if crank had been done ...how do i find out if it has call the dealer?? ....if pics are needed to tell i can email to you just shoot pm ... i have 3 98 srx 600 now and one 99 sx vmax 600 ....so i was thinking of making one bad sled from the three ? just a little part swapping but i want to know for sure if i got a big bore to start with ...thanks for all your help guy
 
get a bendo light and look through the spark plug holes and see if it says anything on the top of the piston, if its a 780 it will have wiescos and numbers on the top of the pistons
 
yes they made a twin 99 vmax 600 which in 98 it was called an xtc600.

The srx 600 and 700 cases are the same.
 
ok i looked at piston but didnt see any thing marked piston wash looked good i think ,,,if it was a big bore would it still be stamped 598 cc with yamaha part number on the jugs or would hauck have removed that?is there any other mods that would have had to been done to make it a big bore different cdi? cause it appears stock to me ..or is that how they were done to not let people know what was in it .... i think the guy was blowing me crap ...or the guy on the phone telling him what was done to it was blowing him crap....someone needs to make a carfax (snowfax) for sleds .....i have emailed hauck to see if they have any record of a kit being installed ...but wont hear back til monday i am sure ..so if anything i have another real nice 600 ....
 
You can always pull a exhaust collar off roll the clutch untill piston is bdc and send a measuring stick accross the cylinder i beleive a 700cc will measure 69mm and i think a 600 is 65 mm or something like that nevertheless a 780 will be in the 70mm range for sure . If you can get a bore gauge its even easier just remove the plug and measure , you will find the bore measurements in the tech section.

Also if it is a big bore and you did not want to pull the heads off i beleive the powervalves will be moded , seeing as you have a bunch of 600 there you can cross check with one of those .


The cylinder stamp will remain the same even if big bored .
 
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Just pull a head off and measure the cylinder, you will know right away what is going on in there. Good luck.
 
ok i have pulled the powervalves come out smooth but they are almost pulled through ..so i need to have them repaired now ? correct ? anyone here doing this for side cash ? i am thinking i am gonna have 9 of them to be done... i took cover off servo and turned it by hand ..one cable broke so when i replace it will the servo go back to were it should be? but i did get a good look at the top of the piston and it is just a flat piston with no markings on it ...so it cant be a big bore ..big bore would be a oversized piston with a size stamped in correct??
 
big bore

Has the power valve been cut down compared to one of your stock valves on your other 600. This would indicate it has been bored out some.
 
ok have pulled the powervalve out of MY srx which i know is stock bore with 3600 miles ...AND NEVER CLEANED POWERVALVES!!!....WAIT I GOT PICS ;)! ... i am unsure of what kind of mod to the power valve is suppost to have it looks the same except the face of the one in question looks like it has been ground down like mabe 10 thousands ? is that what i am looking for? ...back to my sled i have never cleaned the power valve in ..i have olny pulled one come rite out ....but they are alot cleaner than the ones i pulled from the one in question ......
 

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ok i have repaired the valves with a 5/16 stainless bolt and even pinned with a roll pin ...almost tig welded the hole shut but decided not to .when i drilled the hole for cable end i drilled it a little too close to the bottom..so now i will have to loosen cables a half turn or so to make up for this ...but still am unsure if it is a big bore ..power valve looks a lil smaller ...do they cut the face of the valve for a big bore?... almost looks like it face is all silver fresh looking ...and the stock ones all look brand new ...almost a green tint .....pics are above one on left is the one from the (big bore?) one on the right is a stock 600 ....but now that i have cleaned srx #2 do i have to adjust the cables ?? all i did is turn the servo by hand to get enought length..i have turned it back to were it cables are tight ...will it go back were it needs to when i start it up? thanks guy need all the help i can get .......richard
 
thanks hope it is a big bore ....the face of the valve looks like it was ground to match a bigger piston ...that must be the mod to the power valve for a big bore ...can anyone confirm this for sure ?
 
lseehwtohms said:
thanks hope it is a big bore ....the face of the valve looks like it was ground to match a bigger piston ...that must be the mod to the power valve for a big bore ...can anyone confirm this for sure ?
Click to expand...
I would say so...
 
ok i dont have a bore guage but i did stick a piece of wire in there and rolled motor up to just compress wire a bit ...i pulled the wire out and it measures 2 3/4 inches which converts to 69.85 millimeters .....big bore ?? stock 600??
 
YA*AM*A*HEAD said:
thanks hope it is a big bore ....the face of the valve looks like it was ground to match a bigger piston ...that must be the mod to the power valve for a big bore ...can anyone confirm this for sure ?
Click to expand...

yes, the angled/radiused face of the valve is what gets cut. it needs to have the bigger radius cut in it, to match the big bore piston radius.
 
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