Major top end help (with pics)

[ACOLDTO1L3TS3AT]

So a few months ago I purchased a 1994 banshee, bone stock never had any work done to it... compression was relatively good. So the more i ride it, the more the compression goes down, and i mean it was going down fast, till pushing the kickstart was like putting a hot knife in butter and it wont start no more... so i let it sit up for a while and finally get bored, then decide to tear the engine down, and from prior knowledge i knew it was the top end. Pistons fried, head/domes are fried, head gasket blown/messed up, and whats weird is that the cylinder walls are still as smooth as a babys ass, but pistons are to shit, so im not really sure what to do, i know ima get new pistons, new head and gasket, but im not sure if i need a bore job on the cylinder. So what im asking is, if you were in my situation what would you do?

 

Thanks for any help.

 

(dome/head) http://i123.photobucket.com/albums/o301/DioDiSesso/Banshee001.jpg

(piston head) http://i123.photobucket.com/albums/o301/DioDiSesso/Banshee002.jpg

(piston head) http://i123.photobucket.com/albums/o301/DioDiSesso/Banshee003.jpg

(cylinder wall) http://i123.photobucket.com/albums/o301/DioDiSesso/Banshee004.jpg

[Phelps]

i would contact a sponsor and have the cylinders bored. the damage was caused by detonation from either being too lean, or too much timing. improper jetting, or a air leak caused it, so make sure you figure that out before you toast a new topend.

[sheerider1026]

what oil are you using as a premix?? ratio?? looks like something got in there and did the bouncing dance.. i would go ahead and bore it.. maybe get a cool head to bump up the compression some while u are at it... passion racing did my complete topend for like 250.00 everything i needed from pistons, rings, clips and all that..

[BigRed350x]

Send the cylinders off to Kevin at Herr Jugs and get them bored/honed and new top end kit. He has super fast turnaround time.

 

Your problem looks like detonation. What was your compression / jetting / elevation? You were either running lean or had an air leak, or had too much timing / compression for your fuel you were using. Hate to say it, but with what your pistons look like this would also be a great time to split your cases and get your crank checked out. With that much detonation for that long, chances are that your crank is probably trying to separate as well.

 

Give Kevin a call, his number is in my signature. He can get your cylinders bored & honed and hook you up with a new top end kit to match the new bore and get it back to you faster than most of the other guys. He can also take care of your crank if you decide to split the cases and get it checked out. (I would)

 

- Jared

[badassbanshee479]

are you running the stock air box and air filter assy? if so i would either buy a pro design air filter setup for in the air box or buy pod filters. the stock air filters suck and let dirt in the engine.

 

 

i would also contact a site sponser and have your cylinders bored and honed and also have the crank checked out

[midlifecrisis]

I hate to ask, but does that bike have a boost bottle on it? It looks very familiar to my piston tops after it was leaned out and rode on a cold day last year with cracked intakes.

 

It doesnt look to me like a chunk of something came loose and bounced around, the damage isnt bad enough. Split the cases, its that time of year, and get it checked out before it does it again to save a buck. If youre mechanically inclined, buy a clymers manual and do the inspection and rebuild yourself, itll be a good learning experience, and use the forum for advice.

 

Good Luck!

[sheerider1026]

i stand corrected.. sorry.. shouldnt post when im not in my right mind

[ACOLDTO1L3TS3AT]

I run a pint of yamalube to 5 gallons of gas, but imma be honest with you guys, it was sold to me without an air filter and was kept like that... i was running it without one it was street riding for short distances and not a long time though never dirt, and im not sure of my elevation, im in New orleans, La though if that help, and not sure of my timing or jeting either. But about getting it fixed, they have a atv racing shops that mods engines by my house, i called them a while back and they said it $40 to bore each cylinder so $80 total, should i just bring the whole engine in the shop, or bring the whole 4 wheeler in, cause idk if theyre gonna have to start it and test it or what? I just need a little help where to steer when it comes to this, im not too familiar with getting 2 strokes worked on... I dont wanna have to ship stuff off if they got a shop right by my house that will do everything.

 

Thanks.

[BigRed350x]

I would take it to a shop that specializes in banshee's. Give Kevin at Herr Jugs racing a call.

 

If you rode it without air filters you were definitely going lean, and the detonation was probably a result...

[Jereme6655]

We here cant stress enough about using our site sponsors.....we HAVE seen shops that are good at atv repairs/mods wreck a brand new motor. IF you decide against a site sponsor make sure to ask if the chamfer the ports after it is bored.....if they give you a funny look or say no DO NOT use them! Also to do a rebuild which includes replacing the pistons means you must get it bored. If your mech inclined then all you need to take them is the cylinder juggs. They will measure them then order the correct pistons for the sizr they will be boring your clyinders to. They will get you the pistons/wrist pins/circlips as a top end kit. And x2 on getting a clymers manual.....its basically the banshee bible/lifesaver...

[bigboybanshee]

I know where everyone is coming from, saying to use the site sponsers, and you should when it makes sense, but for something as simple as having a bore job done, and you have someone local to do it, I would go the local route. To me, there's no sense in sending it across the country to have something done that your local shop can do. You actually have several shops in your area that can do the work you need. I'd take the cylinders up to the shop and have them order the pistons and bore them for you, and then order the rest of the stuff online from sponsers, like a new cool head, gaskets, etc.

 

I guess part of my reasoning also is I have lost faith in the postal service/UPS/Fedex...I've seen too many damaged parts from them punting your package across the shipping facility, or the courier tossing packages on the doorstep. I do as much as I can locally before venturing out. It's also nice to be able to see the work before it leaves the shop so if something appears wrong, you can have it fixed right then and there.

 

Just my .02

[n2otoofast4u]

You should be pretty close to Titan Racing. He is in MS. If I lived in your part of the country, he is the ONLY one I would use to have your work done!!

[bigblockbanshee]

The only things I would opine with is no matter if a shop is next door to your house, they can still mess it up badly. And it is absolutely necessary to keep all of your machine work with one machinist and make sure that person knows what the crap they're doing. Mixing machine work is a nightmare and only asking for trouble. Pay the extra money and ship it to a reputable builder/site sponsor like Herr Jugs. My brother-in-law just got his jugs back with a fresh bore and hardcore MX port job and let me tell you man they look amazing. Kevin does some killer work and the best thing is that it's consistent and every part and dimension matches from one cylinder to the other. He also had about a week and a half turn around time from shipping it to him to receiving it back. When you ship go with USPS but make sure you package it tight and very well cushioned and you'll have no problems at all. USPS has become one of the faster methods of shipping lately IMO. As far as the bore itself, it may look silky smooth and you may even still see the hone marks (not likely but just as an example) but what you can't see is cylinder warpage. That's the kind of stuff that will ruin any engine quickly and you can only check it/find it by using a bore gauge and checking several areas in the bore. Never ever run without an air filter either for future reference.

[Darthwall]

kevins work is good stuff you wont be sorry

[ACOLDTO1L3TS3AT]

Update: I finally got around to getting it around the corner, the owner of the shop said hell take a look at it and give me a call/estimate sooo... I get a call from him a few days later, and he tells me my piston rings some how broke and the chips/pieces are what caused the damage, for a total top end rebuild-cylinders bored, new pistons, jetting, air filter, and carbs (I knew i would of needed them, i was running without an air filter, yeah yeah yeah) he said hell do everything like tune it and whatnot for me for $900... should i do it? I know its expensive, but i bought it the thing running for $1,000 so i wouldnt mind, i was planned on selling it when it got out the shop anyway.

 

And to be honest, I think hes a bullshitter and someone who think he can rip people off lol... but i got no choice really...

 

Thanks.

Edited February 9, 2011 by ACOLDTO1L3TS3AT