not sure if this is the right area to post up in right now but i have a few questions that can probably be answer pretty easily. im in the process of replacing top end on my yamaha blaster. the piston skirt pretty much shattered and now there is a bunch of metal shards down in the crack which cause the kicker to seize up. i removed most the big pieces by hand and now the crack and the kicker spin freely, but there is still a bunch of smaller shards in there that i would like to remove without splitting the case. Does anyone have a good technique for removing debris with out splitting the case? and now that i have to replace the piston head and bore the cylinder, what is the best way to start this? should i buy the piston first, and have the machine shop bored the cylinder to the piston or should i have the machine shop bore the cylinder and then buy the piston head? im not sure how bad the cylinder is, so i don't know how much it would need to be bore. my guess was to bring the cylinder in first then buy the piston. also what sizes do the piston heads come in? is there a recommended size for first time bore? i wanna make this quad move faster for sure so id like to get some more power as well as room for error incase this happens again. after i get that all figured out will i want to upgrade to a bigger carb? or can i still use the stock one with bigger jetting? any help or advice is highly appreciated and again sorry if this should be posted in another section not to familiar with the whole forum yet.
engine help please
- Thread starter 08curranc
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split the case man...its not worth cutting corners. if you clean it the way you want its very possible you wont get it all. i know this because i had the same issue and it didnt matter how many times i soaked it and prayed it with all kinds of cleaners and degreasers i was still pulling small shards of metal out. trust me dude split the case.
split the cases also boring your cylinder out t max bore will not make a realistic increase in power it seams like more cause the top end has been freshened up and will be very healthy. always always always have the clylinder bored first then buy the recomender piston for it eather wiseco or oem. they go up in incriments of .25 so you'll probably need a 66.25 or 66.50 piston. and the cylinder bore will be .10 or .20 over
No, no, no, piston should be in hand before boring.
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The sad news here is that you have to split the cases, as you will never get all of the debris that lurks in the bearings out.
It is a good idea to replace the bearings because if they have run with any debris in them they will be damaged.
Depending on how much the cylinder has to be bored will determine the size of the piston needed.
Have the shop measure and inspect the bore, they can then tell you what size piston to buy.
It is a good idea for them to have piston in hand before they bore, especially with a forged piston.
Stick with the stock 26mm carb, with your mods it will serve you very well, and can be rejetted.
For more power you need to fit an aftermarket pipe and/or cylinder head.
^2X^ 2X^2X^
When I had my sons Banshee bored the pistons and cylinder came back marked A & B obviously enough difference that he wanted a specific piston in each hole.
Step 1. Take cyl to machine shop. They will measure it. Depending on out of round/taper/gouges they will tell you what size piston to get.
Step 2. Order piston size according to machinist.
Step 3. Take piston and cylinder back to machinist for boreing, they hone the last .0001 for final "fit".
Step 4. Make sure they champher the ports, especially good on exhaust. If they don't, you must do it.
More sad news, you need to buy or make a puller to seperate/refit the cases.
No special gasket needed but you need to use Yamabond or similar sealant.
No special gasket needed but you need to use Yamabond or similar sealant.
Take your cylinder to the machine shop and show them it they will measure up and tell you what size of piston you need then you give them the cylinder and piston and they bore the cylinder to MATCH the piston. Make sure you clean the cylinder well after boring ken occonnor has done a video of it.
As for removing the parts from the bottom end I wouldn't risk running it you could break cases and wreck your new piston and bore for the sake of a few hours I'd just split the cases. I broke mine the other day and they're really not hard to split start at the stator side with the engine out you don't need to go near the clutch side the crank puller really isn't hard to make I made one and as Awk will tell you it wasn't pretty but it worked! Goodluck with the work what kind of piston you thinking off?
And sorry for my bad grammar haha hope you understand
First you either need a Clymers Repair Manual or this http://www.blasterforum.com/general-support-17/downloadable-yamaha-blaster-manual-17325/
That way your BAZILLION questions will be reduced to a couple. Makes it easier for all of us.
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First off i dont know how too read...jk but 2nd if you went to school they encourage more questions because you learn more even with a text book right in front of you. if my bazillion questions bother you just dont respond. im sure there are people on here that dont mind giving there advice and opinions... i appreciate all the help or advice i can get and i like to hear multiple peoples opinions to help me. so again if my questions bother you just dont respond, but i will buy a clymers repair manual so thank you for that.
Do you know of any links or youtube videos that show how to make the crank puller? id rather try and make one rather then buy one. id like to keep this project to a minimum on the $.
WHAT? why would you buy a piston with out taking it to a machine shop to find out what you need in the first place. blaaster, larrys shee yep all the way ........................................................................................................blaaster I can see where our words are criss crosed you obviously want the piston in hand needed for the recomended bore it somehow came out typed the other way arround 8-|
The machinist should have the piston so they can measure it to see what the bore needs to be cut to.
yea deffinatly... sorry about almost blowing up on ya blaaster. long days and not enough sleap will turn even the nicest of teddy bears into a grizz
