1999 Rebuild, will need your help!

[Blaaster]

I started ripping the top cover off already. Carburetor was pretty clean, just old fuel. No ethanol gumming or anything like that. This thing always starts right up first or second kick.


Here are some pictures.

There seems to be a lot of room between the piston crown and the cylinder, or is it shadow?

Does this piston look like it's my problem of the blaster bogging down randomly in the upper gears?

Pistons seldom cause bogging, it is more than likely that poor jetting or and air leak will be the cause.

 

[A7xschecter6661]

Well regardless it has a lot of room as you pointed out. I ordered a whole new cylinder because it's just easier that way.

Where are the potential air leak places on the engine?

 

[harley1-5]

1.base gasket
2.head gasket
3.intake/reed cage gaskets
4.crank seals
5.case halves
6.exhaust gasket/flange

 

[A7xschecter6661]

So would it be worth my time while the whole top end is off to go the rest of the way and change all the engine gaskets?

Everything runs smooth through the gears and all that, the only problem is the bogging down. Couldn't enough play in the piston cause binding possibly causing it to bog down?

 

[A7xschecter6661]

It idles perfectly fine, and usually only bogs down towards the end of the gears usually 3-6. At the beginning of the gears it takes right off

 

[harley1-5]

maybe jetting issue?

 

[Herpderplol]

YES! Change your gaskets!!

You cannot reuse base or head gaskets...

If you got $20 for seals, and $30 for the tools, change your crank seals. If you have a leak there, you will need to anyways

 

[A7xschecter6661]

I am thinking about just doing the whole engine kit, none of the gaskets are in good shape (I wouldn't reuse them anyway). The stator cover one is almost non existent and has let some debris by.

Best thing would probably be complete tear down to replace all seals and gaskets. I don't plan on changing any gears or anything as everything there functions fine.

What's a good complete engine gasket kit?

 

[Herpderplol]

OEM or Cometic are the only ones with worthy gaskets.

NEVER buy green paper chit gaskets....

You can order a kit from http://kenoconnorracing.com/OEM Blaster Parts.html
Top end set
Clutch

 

[A7xschecter6661]

So if I go with this kit

http://www.ebay.com/itm/Cometic-Bot...&fits=Make:Yamaha&hash=item48618cee11&vxp=mtr

And this I already ordered
http://www.ebay.com/itm/181265105084?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2648


I will have every single gasket I need to break the whole thing down and put it back together? It needs it, all around the stator is oily with a fine later of dirt throughout.

I just degreased the entire engine (fully assembled of course) and plugged every hole. Getting it ready to completely disassemble

 

[A7xschecter6661]

After seeing this who else votes complete tear down?



Should I just do the gaskets and seals or do a complete kit like this?

http://www.ebay.com/itm/WISECO-BOTT...Parts_Accessories&hash=item232081e8a9&vxp=mtr


I really didn't want to spend a ton on this thing, but I don't think there is really another option if I want to ride it again...

 

[harley1-5]

I would do a complete tear down.at least you know what you got

 

[A7xschecter6661]

I have it mostly torn apart already, the inside is very clean. No metal shavings, all the gears look perfect and the seals and gaskets did their jobs.

While I am in here I should probably do a bearing swap yes? Obviously followed by all new gaskets and seals.

Just need to get the flywheel off and open up the other half. What's the best bearing for the money? Any decent priced gasket/seal kits with main bearings?

 

[tbrooks]

Do not use a gasket between the case halves. It is recommended to use Yamabond to actually bond them together. Be careful as not enough = air leak or oil leak, too much = have pieces floating around in your engine/gearbox. Yamabond is not actually made to "fill gaps" it is to bond the halves, and so you may actually want to "mate" your case halves. There are some threads on here about it.

 

[A7xschecter6661]

Alrighty so Yamabond, a good bearing set and seal set is what I need.

 

[Blaaster]

Alrighty so Yamabond, a good bearing set and seal set is what I need.

http://www.kenoconnorracing.com/OEM Blaster Parts.html

 

[Herpderplol]

Order parts from ken, he has the correct pieces for everything...


One of the gasket sets you posted was for a wr250, not even a blaster.
The other set had paper gaskets.

Apparently wiseco cranks are not very good, your best bet is to get the OEM one rebuilt (ken also does this) OEM is the best of all cranks.

 

[A7xschecter6661]

Everything I am seeing inside the engine looks fine but I am still going to change the gaskets, seals and bearings.

So if I get the following from Ken:
Koyo Crankshaft Main Bearings
Wiseco Bottom Gasket and Seal Kit

And the top end that I ordered off ebay here:
http://www.ebay.com/itm/181265105084?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649


This will give me everything I need correct? Then I will order my exhaust gasket, carb rebuild kit and yamabond.

 

[dirtysquared]

Yeah that should get you where you need to be. Clean everything well, lap the cases, and label and mark it so you know where it goes.

How's the crankshaft? No use in going to all this trouble, only to have a faulty crank! Getting it rebuilt now will mean you have a totally fresh Engine= peace of mind.

 

[A7xschecter6661]

I am about to pull the cases apart so I will post some pictures of everything