I was out testing the 98 SSX today and have a couple of questions seems to run fine but it backfired when I shut it off to do a plug check after I ran it about 8 miles back and forth across the field. What causes this? The plugs looked to me like they were a little rich but not to bad. The other thing I noticed was that it backfired a couple of times at first until it warmed up good. Is this normal? I am very happy with the throttle response there is no bog at the hit of the throttle. It has the 151.3 main jets and the pilots are 45's not sure if the needles are at the stock setting or not and the air screws are at 1-1/2 turns out. I will probably adjust more on the carbs after I get some more time on the motor would rather it was a little rich during break in. I did premix oil in the gas with the first tank to make sure the oil pump was working also, so maybe that is having something to do with it. The only mods done are the reed valve notching and I removed one layer of my head gasket. Checked my compression today while it was cold and the reading were 110 on the pto side and 115 on the mag side that lower than my MM600 I checked it today and it was 125 on the pto side and 130 on the mag side it has about 400 miles on it since I rebuilt it last year and the only mod it has is a 500 twin cylinder head on it with Wiseco pistons. I am assuming the SSX 600 is lower because of the fact it only had about 5 miles on it so it probably not broke in yet. THOUGHTS? Thanks you
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tedgoesfast
New member
was it warm out mine will do this when its warm out
replace the plugs, you may have a plug cap going bad, or its really rich and you need to adjust jetting....warm outside will cause this also...the rich condition.
harness racer
New member
fuel screw adjustement , and or pilot down one size 42.5's
vince
vince
daman
New member
R u letting it idle down a few seconds or just killing it right away, if just killing it thats why..
Daman that make since because I didnt let it idle down I was going to do my plug check. I did let it idle down the second time and it didn't back fire. Thanks
daman
New member
No problem, i always idle mine probably a minute before killing but doing plug checks yea few seconds should work,let it come down nice.