nate538
New member
Was running at least 20min before hand with a slow ride down the road to get to the trail should be warm by then right
nate538
New member
Just had a friend with a ZR900 have a cold sieze, and the piston he pulled out looks like the twin to yours. But yeh I would say 20mins is deff. enough time for warm up, so prob not a cold sieze.
mopar1rules
Active member
it was NOT a cold seize. it was lean. air leak? plugged jet? wrong jetting?
nate538
New member
mopar1rules I'm glad someone agrees with me lol
I believe missing springs in the exhaust let the pipe push away under throttle causing a lean condition but others say this might not be true the carb will be torn down tomorrow to make sure the problem does not lye there
I believe missing springs in the exhaust let the pipe push away under throttle causing a lean condition but others say this might not be true the carb will be torn down tomorrow to make sure the problem does not lye there
NY_SXR700
Member
That does not look like a stock piston. I have replaced many of them. I don't recall all them numbers on the top and I don't see an arrow. I would check the jet sizes in the carbs, make sure they are stock. Doug
nate538
New member
Engine was supposed to have been rebuilt to freshen it up at 2000 miles it has 4000 on it now so I guess that confirms it
Those pistons look very dry and lean. You should see a brown color and byproducts of combustion. That just looks like bare metal in your pics?
I just took pistons out of a viper with almost 9k miles and they look like they have been in a diesel. I cant believe how bare those appear on top.
nate538 said:
No doubt about it with the exhaust. I melted a ported exciter with a hole in the Y pipe and scorched a 600 XT when the exhaust fell off. Without a question no backpressure equals meltage
YAMAHIZAL700
New member
NO trust me I know all about it. I had a major backfire a few years ago when I owned my polaris ultra and it backfired so bad that the header pipe blew competely off the motor. my ears rang for a week. {no joke!} I had to drive it that way for over 300 miles back to truck so I know all about it. Also on my srx the I had old warn out springs like this guys is mentioning and drove it that way for a while. Other than being louder than it should have been and a loss in performance you could run it all day.BBlueSRX said:
YAMAHIZAL700
New member
Bingo. How bout a leak in the case. YOU NEED TO SPLIT THOSE CASES. I really dont see the big deal at this point. you can clean her all up and then reassemble using yamabond and know your not sucking air there. Also think about all the damaged caused limping it back home in that condition. metal flakes everywhere. It just seems like a way bigger job than it really is.mopar1rules said:
daman
New member
I agree not a stock piston from what i'm seeing,,how does the the other two holes look?
i don't see any exh side detonation melting anywhere going on, oiling issue?
does look lean as hell tho no wash, how does the plugs look post pics.
i don't see any exh side detonation melting anywhere going on, oiling issue?
does look lean as hell tho no wash, how does the plugs look post pics.
Holding it wide open with no exhaust will melt. I agree you can limp a sled around with no exhaust but at higher Rpms its a different story. I thought the springs were missing at the manifold but upon further reading they were missing at the can?
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it look lean and it look like it run without oil ....and almost look like it overheated
YAMAHIZAL700
New member
My bet is who ever sold you this sled knew something was wrong and got sick of putting pistons in so sold you his problem. I bought my srx years ago and thought it was all set. Loaded on trailer headed north and started fowling plugs plus no performance. can you say bad center cylinder. Just to crap on them again. never deal with HOULTON POWER SPORTS IN HOULTON MAINE. They knowingly sold me a junk sled and would do nothing for me. NOw this was over 7 years ago and at that point I couldnt imagine tearing a motor apart dew to youth and lack of knowledge. now thanks to this web site and great group of guys I could rip that motor out and have it split open and sittin on the bench in less than an hour. Moral of the story is that the good news is you got an srx and it can be fixed and you will know what you have and not someone elses headache. also take this as an oppertunity to become a wrencher like the rest of us. GOod luck man! 
nate538
New member
It was missing springs in the exhaust everywhere including the exhaust manifold
I am 90% sure that we are splitting the cases now I was just looking for some other opinions because some people seem to be able to get away with a lot with snowmobile engines
When the other cylinders get torn down today would we see damage there too if it was an oil issue?
nate538
New member
The plug on the right is the mag plug. Definately leaned out the cylinder.
nate538
New member
Can anyone tell me if I am correct in thinking that if there was an oil problem i would see damage in other areas too?
The other 2 heads should be coming off today I will post the pics as soon as my friend sends them to me as I am still away at school.After I see what those look like then we will see if were doing 3 pistons or just one, but the cases are defiantly being split now
The other 2 heads should be coming off today I will post the pics as soon as my friend sends them to me as I am still away at school.After I see what those look like then we will see if were doing 3 pistons or just one, but the cases are defiantly being split now
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