Just Pulled My Cylinder Off... How Does It Look?

[KXDOM]

It looks good to me Id go with the hone and just put in new piston and rings, Unless you want more out of the engine get the bore.

[flotek]

the head design doesnt look right to me ...get some better pics posted of the head/dome itself

[all250r]

It's an 87 stock cylinder. You may be surprised to hear it but it looks like the stock piston which would mean you could be the first person to take it apart. The manufacturer placed ART pistons in from the factory, when picked up aftermarket today the same cast piston says Pro-X in the same spot.

The ports don't look touched and certainly the intake is stock. The ex port looks stock, but it's hard to tell from the pictures. TRX heads are badly designed in terms of peak performance. The squish area is way beyond safe, and teh clearance is so wide it might be borderline unsafe it's so safe.

I think you're looking at a clean slate. You could probably get a few bucks for that cylinder if it were cleaned up! There's a bid for an original bore one on ebay for 175 right now.

[all250r]

Originally Posted by 250r king

run the cr style piston wit the spacer plate in the 88 and 89 mod they have a longer rod get it bored just to have a fresh engine so u know how it runs fresh the jug may also be glazed just hone it and mic it see if its past the tolerance if so or close bore it also buy a adjustable timing plate lots of horsepower from it if timed properly i recomend it it can also add a longer life to a piston if timed right

87's were long rod as well. If' he's at 66mm bore he has until 68.25 before he needs an 86/CR style piston. I wouldn't play with the ignition timing until you know why you're adjusting it. Most importantly though the stock TRX has a lot of detuned characteristics that have well tested fixes that should be dealt with first. What you do and when is just a matter of what you personally want from the motor. It's easy to make it run worse, hurt reliability, or waste your money if you don't know what you're doing. Call builders until you're comfortable that you have someone who listens to you and will give you the best bang for your buck and do it with quality.

[ballzdeep38]

Originally Posted by flotek

looks like your left back tire was running a l ittle low on air

This is strange because the back left tire actually DOES have a slow leak.

[ballzdeep38]

I kinda had a feeling the previous owner didnt do much in the maintenence department there so it wouldn''t come as a shock to find out he never touched it.

The reason i pulled it apart was to go through the top end since i have owned it for about 2 years now and hadnt done it, and i didnt think the previous owner had either. it was also getting hard to start and felt like it was losing compression. just resting my foot on the kickstarter would force it through the stroke. so i figured rings and gaskets would be a minimum.

I was only able to get one more picture of the piston. the only markings i see looks like it says IN on the side towards the reeds. to me it looks like a lot of carbon build up. would this mean it was running really rich?

[all250r]

Originally Posted by ballzdeep38

I kinda had a feeling the previous owner didnt do much in the maintenence department there so it wouldn''t come as a shock to find out he never touched it.

The reason i pulled it apart was to go through the top end since i have owned it for about 2 years now and hadnt done it, and i didnt think the previous owner had either. it was also getting hard to start and felt like it was losing compression. just resting my foot on the kickstarter would force it through the stroke. so i figured rings and gaskets would be a minimum.

I was only able to get one more picture of the piston. the only markings i see looks like it says IN on the side towards the reeds. to me it looks like a lot of carbon build up. would this mean it was running really rich?

Not necessarily. More than likely it means it's seen a lot of combustion. Remember too some oils are more sooty than others so carbon presense by itself doesn't alone indicate rich jetting especially in a motor potentially as old as that one.

Stock TRX's last a long time. See how far the bore is worn. You might be able to get away with .25mm off the bore. Your clutch basket may need attention. New shifter forks can do a lot to improve tranny feel too if they're worn or bent.

[ballzdeep38]

ok so i just took my cylinder to my dads to have him measure the bore. it is a 67mm bore and is within 1 thousandth from the top and the bottom of the cylinder. with a 67mm bore, what will that translate to in cc's?

[all250r]

Originally Posted by ballzdeep38

ok so i just took my cylinder to my dads to have him measure the bore. it is a 67mm bore and is within 1 thousandth from the top and the bottom of the cylinder. with a 67mm bore, what will that translate to in cc's?

253.71828cc. Maybe some others aren't, but I'm surprised you have an ART piston in that motor. Interesting! Have fun with it!