Amongst my dozen riding buddies I turned out to be the mechanic of the bunch and I need some advice as to what is causing this darn Blaster to keep seizing. Both times now has been at Glamis sand dunes when being rode at 3/4 throttle on "sand highway". The bike is a '01 with Trinity pipe, 280 main jet (230 I beleive is stock), one step bigger pilot jet, and the air box lid removed.

After teardown of the first seize about a month ago the piston had a bunch of scratches and the cylinder walls were pitted like a whole bunch of sand papper had worked it. Also, the front top of the piston almost had a hole blown through it and the rings were melted into the piston like it was having early detonation. We had the cylinder bored and a new pistion, rings, and seals were put on.

Now hear is what is bugging the crap out of me. When I put the bike back together I was ULTRA carefull. Everything was cleaned including the airbox, filter, cylinder, carb, and gas tank. Torque specs were followed. The filter was completely cleaned and grease was applied to the under side to eliminate debris getting in. Careful break in was done and the bike was ridden for about five hours after the break in.

Now yesterday the bike seizes again and frankly I'm beside myself as to why it would. I pulled the plug and it looks completely normal. The bike wasn't running lean by the look of the plug. It was completely dry and brown. The only other thing I noticed is that the pipe doesn't look like it was made at Trinity proplerly as it has a slight gap where it hooks up to the exhaust.

So, what's the story here with this bike?? I'm completely confused and stumped and don't want to see another $250 go down the crapper. Thanks for any help or suggestions.

 

I have had a number of engine seizures on my Blaster and Banshee for many different reasons over the years. Because your problem is at 3/4 throttle you may have your needle setting to lean. You need that pipe sealed correctly to work right. Are you using the injection or premix?

 

I have had all kinds of two strokes with all kinds of siezures.
In this day and age, I believe thier's so many ways to protect your self!
I agree with free1steven, but also I agree with the powroll way.
After a rebuild or a bore job or what ever, they tell you to double up on the two stroke oil.
I go a step further, I lift my needle by one c-clip slot and go up two sizes on my main.
They say ten hours on the extra two stroke oil, I put a extra ten on the rich carb settings.
This is all in safety, whats a plug cost!!!!!

The melt down on your piston shows you were the hot spot was, in this case I would go rite to the exhaust.
Seal the exhaust completely.
And yes you were lean, thats how the melt down accured.

Amsoil makes a tranny oil and a injection oil, try these.
Good luck, and take it from experience, if you like performance this won't be your last melt down!!

 

Yes, that's one thing I forgot to add. He is still running the stock oil injection. Is this a bad thing to do? How do you check to make sure it's working?

 

Usualy a stock oil injector has more than enough volume at the lowest setting, but thats for a stock bike.

You can pre-mix a little gas and pull the tube off the carb.
But realy, you have mods and more to come, block off the injection and mix your fuel.
It can be said up to a point the stock injector can be used, but not buy this guy!!

It is also, for jetting reasons, a very good practice to mix the same ratio and use the same type mixture oil to best callibrate your jetting.
It is important to keep a constant on the type of fuel you use.
Me personaly, I would suggest using priemium fuel with some 104 boost, and use the amsoil two stroke oil.
Many will say high octain fuel mixxed with pump gas, not a bad idea, but is costly and has no shelf life.

Thier are many products out thier to use and many are good, I hate to keep bringing up the amsoil, but I have been testing it in three bikes for the last 2 1/2 months and it realy works well.
Now the guys ready to say mobile one, come on buy I've been doing the same testing with one bike and mobile one and if you want me to do it again for you, this time you can buy the clutch

 

I have a friend whose had a blaster for about a year, and once he put his trinity pipe on, he started having the same exact problem as you are, but now since he removed his pipe, it's running great. I think it may be an issue with the trinity pipe. Just out of curiousity, is it the high rev model.

 

You or your friend needs to find out why the pipe isnt seating. That right there sounds to be the problem. Don't blame it on the pipe though unless there is actually a problem with the way the pipe was made. It sounds like it may just be a jetting issue.I would play with the needle and main jet settings and try to get it just a little rich. It is better to go through a few plugs rather than top ends. Also go through the air box and make sure you are not letting mud and other such debris in.Other than that I would say you are just in need of a good rejeting. It sounds like (with a hole almost in the piston) that it is way too lean. Just richen each, the pilot,main and the needle setting one notch and if it isn running good just lean one at a time back a little until it runs good but not too lean. I hope I didnt confuse you at all and maybe helped a little.

 

Gaff,
What are you doing here? Ha Ha
Lakota300

 

Just a few more bits of information I can share to find out what's going on.

The first time the bike seized, the top and front of the stock piston was melted. I tore the bike down last night and this time the piston (Wiesco) and cylinder shows extreem wear on the right and left sides with no damage to the top or front of the piston. Why the differences in wear? Also, I inspeceted the airbox and there was absolutely no debris that got past the airfilter. So guys, what the heck is going on here?

 

make sure to check your rod bearings...maybe after the first melt down you damage them.