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Won't start after engine swap?

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Hey all, 

So I just completed an engine swap, got everything connected and got my battery charged, flushed out my old gas, emptied my float bowl, poured a cap full of engine oil down onto the cylinder, and put a fresh plug in.

It turns over just fine and sounds healthy. I'm getting puffs of air out of the exhaust, and every now and then I'm getting some backfires and pops like it wants to fire. I've also tried bumping it down a hill just to see if the compression was low from some dried rings, nothing.

If I give it a quick jab of throttle and the accelerator pump goes to work I get a thunder of a backfire, so I'm pretty sure the compression is there. I'm just kinda baffled that nothing seems to be doing the trick, the carb was in perfect working order attached to the busted motor before the swap.

 

Only things I can think of are to check timing to see if its off a tooth, valve clearances (Even though I feel like if its minimally out of spec it should still run am I wrong?) and to completely clean out the carb

 

Just wanted to see if anyone else has ran into this headache and what your solution was.

Thanks for any suggestions

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Yeah .. if you get a backfire , it has spark , did you check the valve clearance? . if you say the carb is ok , did you confirm fuel flow .

im a non believer in pouring oil down the plug hole , some do it I know . I believe in no lube above the rings .

 

i am doing engine swap as we speak , I'll be kicking it in the guts .... soon 

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4 minutes ago, NEKOOHC said:

Yeah .. if you get a backfire , it has spark , did you check the valve clearance? . if you say the carb is ok , did you confirm fuel flow .

im a non believer in pouring oil down the plug hole , some do it I know . I believe in no lube above the rings .

 

i am doing engine swap as we speak , I'll be kicking it in the guts .... soon 

Yeah I flooded it pretty good in frustration once haha, when I pulled the plug it was wet so that confirms fuel. It's down to the clearances or if its off a tooth it seems. If it's not that, I'm completely out of ideas.

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1 hour ago, jjktmrider said:

Do you have another new plug ? The standard plug can foul out easily with oil . Is the motor an E and your bike a S or SM or vice versa ? the 2 ignitions are different IIRC .

 

.

I could try that. As for if it's an E, I was told it's an 09 SM, and it has a stage 2 intake cam with a stock SM exhaust cam so I'm figuring it's SM

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So, sorry to revive this pretty dead thread, but just in case anyone comes across this and has my symptoms I went ahead and checked my valve clearances, everything is in spec except for an exhaust which is at .10 :thumbsdn: I think I may of found my reason why it sounds so close and all I get is backfires out of the exhaust and upon further discovery, I learned to take your filter off while figuring this out, I was getting little backfires through my carb..Hopefully the shim does the trick!

Edited by dotpeek

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Yeah .. my engine swap went ok , started 2 kick .. but , I had a pool of coolant on the floor . Took me a while to find the leak , it is a pinhole leak in one of the welds on my mylers radiator . It was fine before I removed it , I didn't drop it ? ... strange

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So I've never timed an engine before, and I only have what appears to be one hotcam which is kinda throwing a curveball, this is how the cams sit at TDC, and I unfortunately can't seem to find any other installation guides or pictures with that exact cam for reference, everything looks to be in order, but correct me if I'm wrong but starting from the exhaust on the right, it should be 15 pins over to the intake where the white line on the hotcam will sit in the middle correct?

IMG_0704.JPG

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