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wogstaa · (This post was last modified: 09/12/2011 05:03 by wogstaa.)

Firstly the problem is the engine cranks over fine, it's not firing at all. I got a massive backfire (with a flash out the muffler) and that's it.

The only thing I can think of is that I sprayed some threebond engine conditioner down the intakes before I did the clearances and I couldn't start it then. It flooded, I pulled the plugs out to clear it out, one broke and I decided to take the head cover off to make it easier to get out and then do clearances while I was at it.

I put the cams back correctly, as per the manual. Which is engine at TDC with the IN mark on the intake cam facing the EX mark on the exhaust cam, both parallel to the cylinder head. I double and triple checked this after bolting the cams down.

I've put the ignition cables back into the right spark plugs.

First problem solved, when I took it for a ride I got a whirring noise that sort of sounded like the cam gears when you accelerate but a little higher pitched and it only happened on deceleration.

Left coil goes to cyl 1 and 4 and the right coil goes to cyl 2 and 3.
I'm getting spark on all plugs and they are brand new.

Carbs shouldn't be a problem, they were fine before and I've tried another known good set from my other bike, still nothing.

It won't even start or fire when I spray some start ya bastard while cranking.

Have I fucked up somewhere?

Pulled the cams again and it looked like the quieting gears on the exhaust cam weren't mating properly, so I've fixed that, should have it ready to test ride tomorrow.

Aduro · 08/12/2011, 02:04

If the cam timing is out by even one tooth on the gears that can screw you.

wogstaa · 08/12/2011, 02:28

(08/12/2011 02:04)Aduro Wrote: If the cam timing is out by even one tooth on the gears that can screw you.

Yeah I know, that's why I checked it again and again. I really didn't want to put it back together and then have to take the cams off again.

I've made some progress, I pulled one of the plugs, it smelled like threebond engine conditioner, so I'm guessing there's still residue in there from that that needs to be blown out.

I pulled the choke and I heard good signs (sounded like it wanted to fire) but my battery is going flat so I'll let it charge up for a bit before I try again.

fatboy · 08/12/2011, 03:03

Check the direction the timing marks on the cams are supposed to face. I seem to remember them facing out.

zane · 08/12/2011, 03:05

they face out

Aduro · 08/12/2011, 03:13

Bump start yo. That conditioner makes for difficult starts til you burn it all out.

wogstaa · 08/12/2011, 03:31

Either way I put them in the same way I removed them, both marks were facing eachother, I put them back exactly the same way.

The manual is strange at times, one point says face in, the other says face out.

Anyway, I've got it started now, it struggled for a bit but now it's idling and it seems to be idling better than before. Revved all the way up to redline fine and was blowing some smoke (I assume that's the threebond conditioner)

Just need to top up the radiator and oil and hopefully that's the end of that

Lane · 08/12/2011, 04:22

Clearances should be done with a stone cold engine, if you were spraying engine cleaner in and messing about with it, you're not getting the most out of each operation.

wogstaa · (This post was last modified: 08/12/2011 23:12 by wogstaa.)

Engine was left for a couple of nights before I did the clearances, because I broke a spark plug and I took my sweet time to get it out without fucking anything else up

EDIT: Just took it for a quick ride, I can't tell if anything is up because I have changed the jetting and airbox setup from the last time I rode it.

One thing I did notice though is that there is a much louder whirring noise when I'm slowing down, sounds very similar to the cam gears when accelerating.
I have gutted the airbox and have drilled big holes in the top lid, could the whirring noise be louder when slowing down because there is less material baffling the noise from the engine?

EDIT 2: It's not the airbox, tried it with a normal one on and same noise.
It seems to do it after the first stop

wogstaa · 08/12/2011, 23:29

I'm gonna pull the cams out again to double check everything.

Is there anything I should look for that may cause the whirring sound on deceleration?

If it helps, it doesn't seem that the cam gears are any noisier than usual when revving up.

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