Blaster Engine Break in

Thanks a lot for posting this, I had some mixed information on how to break in the blaster.

I'll definitely have to do this when I finish my build.
 
learn something everyday.... I didnt know u had alittle daughter... she's a cutey..I dont know how u pulled that off... oh ya u married up...lol
 
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No re-torque needed during heat cycles but I'll check them before the customer picks up his ride. This quad came in for repairs because it wouldn't start. It had 60 # of compression. Once we got the top end off, we found a bad crankshaft as well. My customer wasn't impressed as he just had the engine “rebuilt” earlier this year at another local shop. When we got the cylinder off, we found a snagged ring, cracked piston skirt and no chamfer on any of the ports.
 
That should ease the questions now! I agree with Ken about that infra red temp guage, I was able to get one at harbor freight for $35. One of the best tools I bought! I take it with me on most rides I like to see what is going on after a hard day of riding, Notice he was taking it from inbetween the head fins! Important for a good proper reading!

Thanks Oconner family for saving another blasty motor!
 
Exactly how i did mine this last time except i retorqued with a freshly calibrated snap on digital torque wrench after every heat cycle when it was fully cooled before restarting it.

I just left the tank unbolted so i could easily lift it off.

So far so good!

I dont suggest anyone go by "FEEL" 18-20lbs aint much and its easy to overtorque at those small amounts.I also when initially assembling the engine go half the recommended torque specs until all the nuts are at the same torque then go the the other half.Its something ive always done on any motor ive ever built with no failures to date.Most recent being my supercharged 4.6 daily driver.
 
I just installed my new top end and was unaware of this heat cycle process... Luckily I only gave it one ride so far, the bad news is I let my idiot friend test drive it also and he was attempting to pull 3rd gear wheelies and sorta winding out the RPs for a couple seconds until I flagged him down & stopped it immediately lol. He informed that he did take the motor to full speed in last gear in a field very briefly... My question is how much trouble am I in for now & how much damage might he of caused?
 
Quad King

I believe that the process of heat cycling, is to allow the rings to settle into the fresh cross hatching in the bore by the process of expansion and contraction, without putting the components to excess strain.

As an example the more pressure you exert to the piston crown the more blow by you will produce at the ring lands. It is the pressure that then gets in behind the rings that causes them to expand toward the cylinder walls.

The more they expand towards the cylinder walls, the more they will bite into the crosshatching, therefore causing the rings to grab harder into the cylinder, which can cause problems as they are being gripped by a fresh crosshatching.

If you do the heat cycling, the rings will now be nearly bedded in, ready for the gentle riding which will finish the break in process.

As to the damage, if any, that may have been caused I cannot comment on as some people fang a fresh rebuild from the start and state that they have had no problems.

If it were me I would re tension the head and jug and then ride a tank of gas through at no more than 3/4 throttle, and then let it rip.
 
Quad King

I believe that the process of heat cycling, is to allow the rings to settle into the fresh cross hatching in the bore by the process of expansion and contraction, without putting the components to excess strain.

As an example the more pressure you exert to the piston crown the more blow by you will produce at the ring lands. It is the pressure that then gets in behind the rings that causes them to expand toward the cylinder walls.

The more they expand towards the cylinder walls, the more they will bite into the crosshatching, therefore causing the rings to grab harder into the cylinder, which can cause problems as they are being gripped by a fresh crosshatching.

If you do the heat cycling, the rings will now be nearly bedded in, ready for the gentle riding which will finish the break in process.

As to the damage, if any, that may have been caused I cannot comment on as some people fang a fresh rebuild from the start and state that they have had no problems.

If it were me I would re tension the head and jug and then ride a tank of gas through at no more than 3/4 throttle, and then let it rip.

Thanks for breaking it down into laymans term lol. I get it! And I'm gonna follow your advice with your style of break in sounds fair enough to me. Very informative I'm giving ya some rep I:I
 
thanks for posting this video ken. i did a bit different on my first rebuild on the 03, but when i get ready to put my +4 together i'm going to follow this video.
 
Thanks a lot for posting this, I had some mixed information on how to break in the blaster.

I'll definitely have to do this when I finish my build.
Just finish the breakin period with out killing it. If your friend hurt it let him pay to have it redone. Simple!
 
I'm sure other builders will have other opinions but this is how we do it and it's been working great for years. I see this question asked so many times. Here you go boys.

after doing the heat cycles, allow to cool completely and retorque the head/base nuts


Where are you located. How much would it cost to have my motor built with a couple mods to up the hp a lil. Not trying to race or anything but I want t he power there when I hit the throttle.