It also had the mutlipoint seizer at 1/4 throttle when it happened. Perhaps I need to bump up my pilot and drop the main down. Just a thought.
jetting problems after spending $2000 on mods
- Thread starter turbowrenchhead
- Start date
I'm sure there should be a way to check timing. An induction style light with adjustment knob , mark flywheel and case when at TDC (close as possible) then when it's running adjust light till strobe matches marks and should tell amount of advance. Summit Racing SUM-G1059 - Summit Racing® Timing Lights - Overview - SummitRacing.com
Outside possibility keyway is machined wrong.
Have you talked to Ken about you problem? If so what did he say?
Outside possibility keyway is machined wrong.
Have you talked to Ken about you problem? If so what did he say?
As to the cdi you mentioned, if it's an issue with timing the last thing you want is a cdi that advances even more.
Ok, got the cases together. Let it sit a while and tried a leakdown. The crank collar on the RH side was leaking air between the collar and crank. Do I need to seal this with something?
I took my cylinder and piston to my local machinist. And talked with him a while about the history of the bike. He thinks that there is two problems. The last seize was a cold seize. It was 18 degree weather and crisp out. I ran it for a 10-15 minutes putting around in 1st and 2nd. I started getting on it a little more the next 10-15 minutes. After that I took it on an ice oval trying to keep up with a warrior. I couldn't catch him. After a dozen laps of getting on it pretty good it seized as I was coming up to a corner. I downshift to slow down (more stress on the engine). Is that long enough to have it warmed up?? It is not from a lean burn down. It is a multiple point siezer. He thinks the main is too rich and causing no power increase after 1/4-1/3 throttle. Also I'm pulling the carb bowl after assembled and checking how much fuel flow there is. Perhaps it is a flow problem. But then it would go lean. And I would see a lean burn down condition most likely. Hmmmmm. The key way points to TDC. So I can rule that out. When the bike was stock my 300 pd friend rode it hard trail riding trying to keep up with me. There were several puddles on the trail and he was plowing threw them fast. He also rolled it twice and it landed on its wheels. So it may have lost 2 cycle oil pressure in the stock oil pump. I had no way of checking it since it wouldn't run anymore. It had a lean burn down piston come out of it. Perhaps its possible that the cdi failed and caused this. Anyone have a known good cdi I can borrow or buy cheap for testing? Ultimately I would like to get the performance one available once the problem is found and fixed. Spent enough $$ on this project, I'm running out and rent is coming soon.
And once again, thank you for your input. Its invaluable.
And once again, thank you for your input. Its invaluable.
I have a neon timing light that works off the spark energy to see timing on small engines.
I don't recommend it. Quite dim, have to use it in the dark!
Timing lights are good for checking timing advance or comparing moves.
For the most part you move it to see what it does, and we have the mark for comparison.
As for the aftermarket CDI, another farkle will only compound the problem.
There is a theory of troubleshooting of putting everything to normal first.
Setting everything to "known good" positions.
The further you get from "known good", the more trouble you will have with solving problems.
Better to incrementally modify a machine than to throw a dozen mods in with a rebuild.
If it doesn't work, what was it? The rebuild or the mods? It takes a good man lots of time to track it down.
Please don't take this opinion the wrong way.
It is just a suggestion from years of experience doing things just as you have.
I do things one thing at a time and when something goes wrong, I know what did it.
So, back to questions.
Multipoint (4 corner sieze) is usually only loosely related to mixture.
Has to do with the piston growing too large for the hole.
Usually because of the piston becoming hot inside of a cold cylinder, more common with forged pistons and water cooling.
Too lean a mixture will overheat the piston fast when it is worked, but it can happen when it is rich too.
Either not enough warm up time or sized too close to begin with.
So, I agree with your machinist's thinking.
As for fuel flow, the stock Blaster has enough for over 50hp. It is not a problem.
I run long WOT stretches with the KTM with no sign of starvation.
Good going on the cases and yes, a dab of Yamabond under the collar.
I don't recommend it. Quite dim, have to use it in the dark!
Timing lights are good for checking timing advance or comparing moves.
For the most part you move it to see what it does, and we have the mark for comparison.
As for the aftermarket CDI, another farkle will only compound the problem.
There is a theory of troubleshooting of putting everything to normal first.
Setting everything to "known good" positions.
The further you get from "known good", the more trouble you will have with solving problems.
Better to incrementally modify a machine than to throw a dozen mods in with a rebuild.
If it doesn't work, what was it? The rebuild or the mods? It takes a good man lots of time to track it down.
Please don't take this opinion the wrong way.
It is just a suggestion from years of experience doing things just as you have.
I do things one thing at a time and when something goes wrong, I know what did it.
So, back to questions.
Multipoint (4 corner sieze) is usually only loosely related to mixture.
Has to do with the piston growing too large for the hole.
Usually because of the piston becoming hot inside of a cold cylinder, more common with forged pistons and water cooling.
Too lean a mixture will overheat the piston fast when it is worked, but it can happen when it is rich too.
Either not enough warm up time or sized too close to begin with.
So, I agree with your machinist's thinking.
As for fuel flow, the stock Blaster has enough for over 50hp. It is not a problem.
I run long WOT stretches with the KTM with no sign of starvation.
Good going on the cases and yes, a dab of Yamabond under the collar.
I ordered a flywheel puller and I have main jets from 148 to 205. Pilots from 48 to 60. I'm going to spend all day out at the lake if I have too to get it right. I have a regular timing light that works well if you hook it up to a charged battery. I have a spare one that I can take along and I can see if changes to my timing will make a difference. I'm taking a dozen plugs along with and label each one on what jets and chopped them back home with the cut off wheel.
I will prevail!
I will prevail!
Have you primed the oil pump since the rolling, if not this could be the root of your problems, no oil!
I think you might have hit on your problem I:I.
1. With having heavy mods you should have switched to pre-mix.
2. I think you might have cold seized it. Not from lack of warm up or lean jetting, but from actually OVER cooling. My son seized his on the lake WOT 6th gear, had to have been at least 0*f that day. Was no damage to crown, but ripped metal from piston and stuck it to cyl on ex side. Started jetting it was only maybe 25* and went fat. I wracked my brain over it. Jetting? Oil pump failure? Oil got to thick to pump? It was something I read on here that got me to thinking, then looked at a linc for piston pics. Bore looked good other than stuck alum.
Hope this novel helps. I:I
1. With having heavy mods you should have switched to pre-mix.
2. I think you might have cold seized it. Not from lack of warm up or lean jetting, but from actually OVER cooling. My son seized his on the lake WOT 6th gear, had to have been at least 0*f that day. Was no damage to crown, but ripped metal from piston and stuck it to cyl on ex side. Started jetting it was only maybe 25* and went fat. I wracked my brain over it. Jetting? Oil pump failure? Oil got to thick to pump? It was something I read on here that got me to thinking, then looked at a linc for piston pics. Bore looked good other than stuck alum.
Hope this novel helps. I:I
As I have stated before I run premix 32:1 with super m oil. No more oil pump. The machinist thinks its too rick because of the piston carbon buildup. Its clean around the intake side, thats from raw fuel washing away the carbon. It should be an even brown/black color covering the whole head of the piston.
When I warm mine up in the cold weather, i stit on if for a good five to seven minutes varying the rpms, then I reach down and with my infrared gun i see what temp it is at I don't ride it till it's over 180 degrees. I also do as you do a put around for a few minutes at various rpms, then I take off! After I've ridden it for while i use the infrared again at i'm always at 195-205. depending on outside temp.
If your not letting it warm up before you put a load on it, I believe that may be your siezure problem.
If you have access to another coil and plug boot I'd swap them in and see. Sure does sound like an intermitent spark issue.
If your not letting it warm up before you put a load on it, I believe that may be your siezure problem.
If you have access to another coil and plug boot I'd swap them in and see. Sure does sound like an intermitent spark issue.
You're quite a bit more careful than I am. I let it idle until it idles back down on choke and then turn the choke off and GO!. Generally wide open at that point too!
I've never had a 4 point seizure....I run my forged piston on the tight side, and I'm jetted on the raggedy edge! *sings* "he's a maniac, maniac on his blasty!"The fuel "washing" the crown is normal for a slightly rich engine... nothing that should have caused a problem.
Thats a good idea. It would have to be a timing issue since it has never misfired. There have been times when I got on it and it sounded very tinny and rattly. I don't know if it was it detonating or what. It sounds like the reeds are flapping rapidly but I know that they are not going to make noise. The piston didn't show signs of detonation either.
I've had so many coil issues I lost count!
BTW I can let ya borrow my sons cdi for troubleshooting if ya need it, his isn't gonna be running anytime soon! I do believe that two of those coil issues were the plug boot! I have since bought the NGK boots and haven't had an issue knock on wood!
BTW I can let ya borrow my sons cdi for troubleshooting if ya need it, his isn't gonna be running anytime soon! I do believe that two of those coil issues were the plug boot! I have since bought the NGK boots and haven't had an issue knock on wood!
I did find the original one was 6.3k ohms and out of spec. I bought a new oem one and it ohmed out at 4.2K.
If it still has problems after the fixes that would be cool if you let me borrow it.
If it still has problems after the fixes that would be cool if you let me borrow it.
So it passed the leakdown test now. I started assembling the rest of it and thought I better check the shifter. It wouldn't go into 4th gear. I tried and tried while turning on the output shaft. It just wouldn't go. So I had to pull it apart again. ARGGGGGGG! I got the case split and I don't see anything wrong with the transmission but it still wont go into 4th while apart. It wants to lift up on the shaft when trying to put into 4th. I had enough for tonight. My brain hurts.
The reason why i won't tackle a bottom end! too much for me to get wrong!
Hope ya get it all figured out!
Did you lube the fork and shaft and it slide or was there actually something wrong?
I've had them "sieze" after a cleaning and not want to slide on the shaft. I've got into the habit of dabbling a little transmission fluid on the slider shafts now before I let them sit any length of time.
I've had them "sieze" after a cleaning and not want to slide on the shaft. I've got into the habit of dabbling a little transmission fluid on the slider shafts now before I let them sit any length of time.
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