Topic: K0 750 "poof, poof" backfires; I may have overlooked the obvious......?

[zoo mob]

So, many months ago I got my K0750 back from getting some carb work done....but it had this terrible poof, poof, poof backfire. I dorked around, tried to figure it out, kind of got sidetracked with other projects etc. After many ideas as to what it was, I'd decided it must be the intake boots. So I ordered some wintergreen oil and xylol and was going to try and swell them back to original shape. Then I lost the oil. So I finally just ordered new boots. $80 later, I go the boots and went to put them in tonight. While taking the carb tops off, I noticed that the #3 top was not screwed on tight. Tell me this was the problem all along. Could this have been what made it backfire? If so, I've got some intake boots for sale for cheap.

[Spanner 1]

My quess would be any air sucked in thru' the cap would not carry any fuel from any jet to go with it and would certainly lean out the mix to maybe producing popping back thru' the carb.... anyone else?

[zoo mob]

Eyebrows raised "yes it was backfiring because of the cap and you're a dumbass" or eyebrows raised "no that wouldn't cause it to backfire"?

[scottly]

"poof poof" backfires makes me think flooding: too much gas! That's my guess...

[Spanner 1]

Prolly ' eyebrows raised' at any suggestion by me 

[Johnie]

Zooy...do you have rubber seals under those slide caps? My KO came without them and I installed my tops without them until I noticed in the parts fische they should be there. I added them and I saw one of mine was not screwed in all the way either. I still get a little poof, but the plugs look good and she runs so fine at idle, medium and high speeds I am not messing with it. I do admit she runs better with the new rubber slide cap seals though.

[zoo mob]

Well, I'm going to put it back together, try a sync and see if its still a problem.

[Spanner 1]

Please overlook 2 of your replies so far.. ( this is my third ).

[zoo mob]

Johnie, what's the part number for those rubber seals? Can't seem to locate anything other than unavailable carb top kits on the fiche.

[scottly]

What do your spark plugs look like? (you may be overlooking the obvious, as you have already stated  )

[andy750]

Make sure you have the coils set up correctly with 1 & 4 and 2 &3 going to the correct plugs. If not you will get the "poof, poof" backfire.

Good luck
Andy

[Johnie]

Johnie, what's the part number for those rubber seals? Can't seem to locate anything other than unavailable carb top kits on the fiche.

My seals came with the K&L carb kit #18-2421. Those seals are used on the KO & K1. They come cut for the K1, but there is a slight indent in the rubber which shows you where to cut for the KO. The actual KO OEM #16171-275-004. The K1 OEM #16110-300-004.

[zoo mob]

Well, this never seems to get better.......stripped out one of the vacuum bolt holes. I'm over these carbs for now. Picking up a rebuilt set of later carbs this weekend and skipping the hassle until I redo this bike the way I want.