lets play a game!.... help the noobie

[turboaddict]

alright guys i just purchased my first trike...... a 1985 yamy tri-z.
i took it out today for shake down runs and it has stopped running. no compression so i tore it down tonite to examine the "fresh rebuild " it had done. he said it had a weseco piston installed, but it doesnt look like the ones ive had in bikes in the past.
take a look at the pictures and let me know. also it has a pipe on it is it stock? and finally do the reeds look aftermarket? ... i just need help id'ing the part first so i can get some money back from the guy , and secondly so i know what the trike has on and in it ...
thanks for your help
will

[Yamahauler]

Not sure about the piston, but the reeds arent stock, they look like boysen reeds. I'm pretty sure the pipe is aftermarket too, I dont see a heat shield.

BTW :welcome: to the forums
Got any pics of the Z?

[turboaddict]

yeah no heat shield or provisions to mount it...

[Yamahauler]

Yea, looks like an old DG possibly. Definatly not stock. I have an aftermarket pipe for a Z, no idea what brand though.

[Billy Golightly]

Kinda hard to tell with the mud splattered on the pipe but I'll go with an old DG for now too. Reeds I'm 99% sure are boyesen. Piston, look for a W with an oval around it on the underside of it. If its got that its a Wiseco for sure.

[Yamahauler]

I'm pretty sure thats a weiseco piston too. I looked at mine and the W with an ovel around it has a oil hole drilled through it. Looks like that one's the same way.

[turboaddict]

yeah good ! it does have the wwith the oval. any way to id if its oversize??? what is the stock bore size? the pipe was shiny black and cone sectioned. no distinguishing marks on it tho.
thanks for your help guys!

[Lomax]

on the top of the piston will be some numbers to indicate the bore like .25 or .050 something to that affect.

[TimSr]

on the top of the piston will be some numbers to indicate the bore like .25 or .050 something to that affect.

Actually it will have the model number beginning with 515M or 515P. The old style (515P) also has the overbore size in mm (.25, .50 etc.) The new style (515M) I dont think has the overbore amount, but the last 4 digits indicate the bore size, i.e. 6725 = 67.25mm bore.

[turboaddict]

it has the w in the oval on the bottom, and 515 but nothing else. on the top 2 sets of numbers: 5487k
515m06625 but also could be
515m06825
so is this a overbore or stock or what? im trying to get rings for it and make sure that its the piston for the cylinder bore .

[Bryan Raffa]

68.25 would be the first bore over stock! the reeds are boys.power reeds

[turboaddict]

so stock bore is 68mm ?? i think they may have installed the wrong piston for the bore is the only reason i ask....