new to me blaster few questions.

[crash]

Just picked up a 88 blaster. I bought it nonrunning the cdi box was removed and told that was the problem. the bike is pretty hacked up the key was bypassed and was told to use the on off switch to kill it. I just hooked up the old cdi box and i got spark. i turned the kill switch to the off spot and still had spark.

question #1 should I still get spark with a bad cdi?
question #2 should i still get spark with the kill switch engaged?

 

[Larry's Shee]

Just picked up a 88 blaster. I bought it nonrunning the cdi box was removed and told that was the problem. the bike is pretty hacked up the key was bypassed and was told to use the on off switch to kill it. I just hooked up the old cdi box and i got spark. i turned the kill switch to the off spot and still had spark.

question #1 should I still get spark with a bad cdi? Uummm , no
question #2 should i still get spark with the kill switch engaged? Uummm, again no

Good news is that you have spark !! On a Blaster both the kill and key switches go to ground in the OFF position. So either switches are bad or wiring harness.

 

[crash]

I really didn't think so but i had to ask. Im about to check all the wiring thats left. Clean the carb, check the reeds.

 

[crash]

I need a new piston. Probably just new rings. Is the piston measured in MM? should it be stamped? it has a 280 jet

 

[Blaaster]

I need a new piston. Probably just new rings. Is the piston measured in MM? should it be stamped? it has a 280 jet

The piston is measured in mm.it would pay to have the cylinder measured for out of round and taper.

If there was a 280 main jet in there there should be an aftermarket pipe on it.

 

[crash]

Yes it has a aftermarket pipe. Was told, its bore 3 over, aftermarket carb(im thinking is stock due to the tiny nonchangeable piolt circut),Extended swingarm, and its stripped of alot' weighs nothing. I was expecting the cylinder to measure 66.75mm after research. but i guess ill just find a place to get it rehoned and checked out and give me the proper piston.

 

[crash]

I found a guy that will hone the cylinder and get me a piston. He estimated $80 over the phone seems fair.

I also have a 26mm oko flatside carb. The stock carb has all that nonsence on the top that has been long ago disconnected. I assume that has to do with the tors? but it has electrical tape holding it together so I didnt want to mess with it till i get a proper throttle cable it looked like my carb might fit need to research that more.

 

[crash]

I removed the cylinder. I will be splitting the cases. The intake side of the piston skirt was missing.......
Hopefully the cylinder can be honed it does not have and gouges. I could not find a caliper but my tape measure says it might be stock it might just get bored idk.

 

[Larry's Shee]

Unless (which is highly unlikely) that the bore is perfectly round and straight, I would not waste time and money putting a new piston in. Spend the few extra dollars and have it bored to next size. You're only looking at another $50-60. Then it will be perfect.

 

[jbuckster07]

I found a guy that will hone the cylinder and get me a piston. He estimated $80 over the phone seems fair.

If thats for the hone job AND a piston, back away slowly... I think the cheapest piston out there is a Namura, around $60. If taken care of, properly maintained you should have no problems. Others on here will only used forged Weisco and to each their own. Weisco pistons can be had for around $80 on ebay if you can find them.

Do what Larry said^^^^... Dont just get a hone job, bore it out to the next size to make sure its perfect. Also DO NOT give the shop the cylinder without giving him the piston as well. Too many times people have their cylinders bored to the next size and then order the piston only to find out its not a perfect fit when the skirt snags the intake port and shatters, just like yours is now.

 

[crash]

Thanks all. Well I did find a local small engine displacement shop that will bore it for me. I forgot to ask if they will give me the proper piston as well. I assume they will. So i am taking the cylinder there to be bored. Should i just go up the next size or punch it out as much as i can? Will it make that much of a difference if i just go to the next size up instead of the largest I can go?

 

[blasDa]

It needs to be bored to the size required of the new piston. You cannot get it bored without a new piston. If the shop tells you they can bore it out, THEN get a piston to match, run, run fast.

Also you will get no gains by maxing it out. Go to the next possible size required to clean it up, & match the new piston. Then when you have to do it again in the future, you can just get it bored again rather than having to sleeve it.

 

[Larry's Shee]

Tolerances on piston to cylinder are VERY,VERY close. IIRC. .003" for forged and .002" for cast. If it's to tight it will seize, if it's to loose a brand new piston will slap.
Because of manufacturing tolerances the new piston has to be in hand so final honing can be precise !!

While .003" isn't much, when the engine is at operating temperature there is almost ZERO clearance between the piston and cylinder, just enough for a film of oil.. Even at room temperature a piston doesn't want to slide in a cylinder without any oil.

 

[crash]

Thanks all for the info this forum is great. I kinda felt tricked about the pricing of the bore job and all but it is getting done correct. The name of the piston I cant remember but it was a recommended one that I read on here.
So im getting into the bottom end is there a good kit that has all the gaskets, seals, lock washers included?

 

[jbuckster07]

you can buy a weisco bottom end kit, should have everything you need. If it doesnt, I order my lock washers and stuff like that from kenoconnorracing.com

 

[crash]

I thought I would share the homemade exhaust I have to deal with. It will not come out that frame for nothing they had to of welded it together in the frame lol. Im going to clean up the cylinder when I get it back open up the exhaust port a lil bit ect. Then I remembered this beast of a exhaust it must have 12 90 deg. bends :/

 

[crash]

Im sure My expansion chambers functionality is long gone, but Im not really to sure......
I am waiting on a 27mm stator puller. Then I think I will Have everything to do the tear down.
I still need to figure out aftermarket carb options.
About what size carbs run on these things?

 

[jbuckster07]

why aftermarket carb? The stock carb is a great carb, well designed and functions well for some built motors. find a decent used csarb on ebay, clean it up and put it on.

 

[Larry's Shee]

Stock carb is 26mm , a 28 fits stock manifold and filter boot. Little bit of upgrade.
I'm ported and Fat Bastard pipe stock carb and it works fine. Yeah, I might be leaving a bit on the table but it's high stung enough and fast enough for my old azz.

 

[crash]

My concerns with the stock carb is all that extra junk on top of it(Mines taped too). But my main concern is the pre set pilot..

Do I have to buy a throttle cable if i want to use a 26mm oko carb?