Author Topic: Engine backfires and cuts out  (Read 135 times)

Husky Steve

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Engine backfires and cuts out
« on: June 28, 2020, 06:05:53 AM »

I have just encountered a problem on my 2020 se300. Rode for a couple of hours with no apparent problem other than an occasional flame out, which was unusual. Then on my home as I got back on tarmac, it just died.  First I thought fuel, so turned it to reserve. Started up and ran for a 100m and died again. Checked the petcock. OK. Started up and travelled about 6 miles home, ok. Washed the bike. Started it up to oil the chain and it wouldn't rev, it bogged, backfired and cut out. Now it will start, idle, but won't rev. It just bogs, backfires and cuts out.  It has 25hrs on it, so I though, repack the muffler, which did have a fair amount of spooge in it and I am going to fit a new spark plug. I haven't re-started it yet. What else should I be looking at?

Ps. I normally leave it in one map/power valve setting, but I did switch the maps a couple of times on that ride, but can't say that I noticed any difference. Could there be a problem there?

Is the spark plug gap 0.7mm ?
Are the carb settings the same as the 2018/9 for tuning?
Also I can't find the float level measurement.
Thanks in advance. Any help would be appreciated.

Husky Steve

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Re: Engine backfires and cuts out
« Reply #1 on: June 28, 2020, 01:41:34 PM »
Just found tis info on float and carb adjustment for all Keihin carbs.
https://www.keihin-na.com/assets/1/7/slide_valve.pdf

Husky Steve

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Re: Engine backfires and cuts out
« Reply #2 on: July 01, 2020, 12:09:56 PM »
I removed, cleaned the carburetor. Adjusted the float. Set and fitted a new plug. Replaced the muffler packing. I also stripped the petcock as it was extremely stiff to turn and leaked while you turned it. It now moves freely.
Started up and ran fine. Haven't ridden it yet. I will be going out on it tomorrow. I hope to report that all is well. I'm taking a tow strap though. 👍