KR-1S.co.uk Forum

i also forgot to add that now and again both barrels seemed to be working and the power would return, but then it would go again just as quick as it came.

sound more likely electrical then.......as above check stator, coils n plugs....pos cdi but i doubt it...gotta b one of em...

Hi, it's been a while since I’ve been on here and to be honest I’ve been flagging a bit in getting the bike sorted. While speaking to my friend he mentioned maybe the fuel tap being blocked, if that was the case would it of caused these problems? and if so does anyone know where i can get one cheap? cheers

could be the fuel tap, switch it to prime with half a tank of fuel and see if it flows from both spouts? if so try the bike on prime...

I run mine on prime all the time..

stator? if it has nipped up you may get away with cleaning the bores with a light emery rub(if its marked the plating) or if evidence of molten alloy appears then acid can be handy. a new pioston/rings etc should see you right but id be inclined to give it a full rebuild as the cranks seals are prone to fail after long periods of standstill. its not forced to be this tho, could be something minor even a loose/faulty plug cap! i would check the ignition over.

out of interest what was the fault after because i've got a similar problem and can't fix it. Luckily i was planning a rebuild now anyway.

Lol just found out the problem was the crank seal going and a piston getting partially chewed in the process. Luckily those RGV converts are in and ready to go.

well finally got round to having a look at the bike, checked the rings and they seemed to be fine, started the bike up and as before it was running on one cylinder, I then removed the spark plug from failing barrel and checked for a spark which it did have, but a very irregular one so I’m going to get the stator checked over, I’ll keep you posted

I had a similar problem at the track last year. Bike started cutting in and out and the plug colour on one side was much darker and greener than the other. Looking behind the bike I had a load of smoke coming out one exhaust whilst the other ran fine. Bike started and idled fine and fuel and oil supply seemed fine. Had a guy approach me in the pits and suggest I had a crank seal gone and of course he was right. The extra smoke was from burning the gearbox oil and colouring the plug accordingly. Have only just recently stripped it and both seals looked like year old donuts. The outside seals looked good but would suggest replacing all. Sam from BDK is supplying and was fast and easy to deal with. Unfortunately it means a complete strip as you have to split the cases to get at the crank. Crankseals not are apparently quite common on the KR1.

Hi Gizzard...

Strangely I have a similar fault after completing a rebuild... Haven't had it out on the road yet... but it starts first kick, idles fine... but smokes on the right hand exhaust, not the left... Is this similar to yours?

What colour should i be looking for on the spark plug and which Cylinder???

Cheers


Nate

P.S. about to start checking everything else in the mean time

Nate
sorry only just seen your post......how did you get on?

Bummer to have this happen AFTER the rebuild.

If the smoke clears it was probably only two stroke from the rebuild but mine showed a greenish tinge from the green gearbox oil and wouldn't go away after two 15min sessions on the track.

Also beware that if one of the outer crankseals leaks the opposite happens and the faulty cylinder will smoke less (if at all) as the engine is sucking in air and burning lean (can also be caused by any air leak downstream from the carbs as well). Give it a hand full in this condition and it'll eat a piston.

PS it'll take ages to clean all the molten alloy out from the crankcases, cylinder and exhaust and you run a high chance of distroying the crank as well.

This is exactly what happend to mine! was running fine then started to loose power pulled into the pits smoke was pouring out of the right hand exhaust, sent crank to bdk the seals were totaly shot! Also when I started it up today (first time) since rebuild smoke was pouring out of both exhausts, probably due to me using a lot of two stroke oil during rebuild & the oil residue from the blown seals! but it has cleared up now. although I expect it to smoke a bit more once I can get the exhausts really hot.
So dont worry Nate, think it will be ok, just get out there & ride it

Well Mine suffered a simular fate. Engine would be fine for ages then the LHS would not smoke much while the RHS smoked loads. Not using an gearbox oil so I guessed it was the outer crank seals, Wrong.

New seals fitted, engine rebuilt, BANG . Crank rebuilt, new pistons etc. Took it out for its first run, every thing fine, then BANG . Stripped down to find that the engine had nuked it's self on the LHS and left a hole in the piston as that side was running lean. Checked all the common parts for a fault and can't find an air leak, crank seals ok etc. After much head scratching that left me looking like a monk , I eventuatly found the cause.

The LHS bottom crack case at the rear wasn't flat and dropped about 0.32mm in the middle. The engine was running fine until the sealent blew out of this gap, and allowed the cylinder to suck air and nuke it'self. Thing was it must have been like this for 18 years but was fine when using the original Kawasaki sealent, but the newer stuff I use now obviously can't fill that sort of gap for long.

Used Devcon liquid titanium to raise the crank case face and machined it flat once dry, and all is now well. Just goes to show that if its possiable to go wrong, it will and never in the obvious way.

have you sorted the problem yet clem