nicketynoo

No more work required , have just been on a 20 mile blast and the bike is transformed, its running just as I remembered my old one did in 1984. It was great fun to ride and took me back 30 years. Thanks for your suggestions and support guys I'm one happy man!

And todays theory is?? Right just been for a new plug and some fresh 2 stroke oil. Whilst at the shop asked the mechanic to have a listen to her, and he says it sounds really choked up as though it can't breathe. Also had a look at the plug and this confirms its got too much oil. He suggested draining all the old 2 stroke oil off and fill with new since I didn't know what was in so have got a decent semi synthetic going in soon. I'm currently draining the tank now, whilst waiting I decided to remove the wadding from the baffle. I have also checked the setting on the oil pump and that is correct. Ok so whilst waiting I got impatient and started the bike with no 2 stroke going to the pump, I have run it now for a good 10 mins and it sounds like its breathing better and is still smoking. Therefore I have come to this conclusion:- The crank is full of oil/fuel from when the right hand side crank seal was knackered and so needs burning off or emptying somehow. It all makes perfect sense now and I'm really surprised none of you picked up on this . Come on the clue was in the first post So unsure of what action to take now don't really feel like stripping it back down at the moment so any thoughts Cheers Nick

Air filter is now drying on a radiator after a good wash out with fairy liquid. Have tried running with the needle in the carb down a notch and also with airfilter removed but still the same. I'm starting to fear the worse and suspect the knocking is possibly the big end! Have still got to try a new standard plug tomorrow as dont know if the iridium one is correct. If thats no better then I can see me stripping the engine down.

Thanks Tony Thats a very valid point about the airfilter I did squirt plenty of filter oil on it so that could well be a problem, I checked the main jet and it is #120 I don't think anything was done to suit the cone filter, thats the first thing I checked when I put it back to standard. I've just fitted the new piston and been out for a run and although it seems a bit better there's still something fundamentally wrong. It still wont pull in fourth and up. At least I can now see a dry plug and it is grey in colour, I would hope for a coffee cream colour if the mixture was correct. The wadding is still on the baffles and they are in perfectly clean condition as is everything else as its only done 3.5k there seems to be a knocking sound around 6 thousand revs , I have a suzuki rgv and it was similar to this and I raised the needles in the carbs a notch to lean it out and it made such a difference,may go and have another short run without the airfilter. thanks Nick

Thanks Blackhat I'm definitely heavier but not enough to cause this, I can still get up to 60 on my sons aprilia RS 50 admittedly thats laid on the tank with me feet on the indicators, but somethings amiss. Hopefully new piston will be here today and then I can start tinkering.

Hi Have bought a RXS 100 and its really not running well. Firstly I'll give a bit of background about the bike. Its only done 3500 miles from new since 1989 and I believe this is correct due to previous MOT's and the condition of parts etc. When I got it someone had butchered the airbox and fitted a cone filter to it , so I fitted a standard airbox with a brand new original airfilter. The spark plug is a BR8HIX Iridium (not sure if this is the equivalent of a standard plug) The bike starts really easily and has plenty of compression and ticks over nicely but when running it feels as though its choked and won't rev out in any gear above 3rd. The max speed I achieved was 45 Mph which if I remember back to 1984 when I last rode one of these is pathetic. I checked the plug after a decent run and it was very wet which indicates too much fuel which concurs with the way the bike feels when riding it. I have stripped the barrel off and the piston top is quite black and there is a bit of burning past the rings at the exhaust port side which I think is normal,there is a small mark in the top of the piston again at the exhaust side , as though something small has hit it but really not much to affect running. A new piston kit is now on its way. The small end bearing is in perfect condition but this will be changed too. There is no play in the big end and bearings all feel fine. I have stripped and checked the carb and everything is standard (main jet,pilot jet , needle clip on no.2 etc) Not sure how to check the float height but looking at the line on the floats they werent quite horizontal so have set them so they are. This meant that the height was too small therefore more fuel in the bowl ( not sure if this would cause the problem). Also the only other difference from standard settings was the air screw was only 2 turns out instead of 2 1/4 . I have recently changed the crank seals as the gearbox oil reaked of fuel and pretty sure the seal on this side is fine, also I think if the seal on the flywheel side was passing this would let air into the cases and cause the opposite of what I've got. Any thoughts or pointers to look out for would be appreciated Thanks.

Thanks for the replies I will change the left hand seal at the same time. Kev I have still got the engine in the frame and to check the mains I'd have to split the cases. I'm pretty sure they're ok though. This engine has only done 3.5k and I reckon the seal has gone due to standing so long without being used. The fuel definitely hasn't come from the carb flooding and so flooding the crankcase. Thanks again Nick

Hi Ive recently bought a very low mileage 1989 rxs100 and have only ridden it less than 1/2 a mile but it seemed a bit sluggish. I've found the airbox has been butchered to fit a cone filter and holes drilled all over it. ( looking for a complete 1 if anyone has ) The carb however hasn't been jetted to suit as its still running a standard 120 main. The main issue I've got is I've dropped the gearbox oil and its full of fuel!. I take it the reason will be the right hand crank seal ? I've stripped this out and a new 1 is on its way. I've stripped the left hand casings off and theres no sign of fuel behind the flywheel. Can I take it this side seal is ok. I'm thinking of just replacing the right hand seal and seeing how it goes. Any thoughts would be appreciated thanks.

Hi Ive recently bought a very low mileage 1989 rxs100 and have only ridden it less than 1/2 a mile but it seemed a bit sluggish. I've found the airbox has been butchered to fit a cone filter and holes drilled all over it. ( looking for a complete 1 if anyone has ) The carb however hasn't been jetted to suit as its still running a standard 120 main. The main issue I've got is I've dropped the gearbox oil and its full of fuel!. I take it the reason will be the right hand crank seal ? I've stripped this out and a new 1 is on its way. I've stripped the left hand casings off and theres no sign of fuel behind the flywheel. Can I take it this side seal is ok. I'm thinking of just replacing the right hand seal and seeing how it goes. Any thoughts would be appreciated thanks.

Thanks for the tips and the welcome guys. Have been a while replying to this as my laptop has been inundated with malware and havent been able to sign into the forum. have had a search and found the Yambits site pretty useful. Thanks again Nick

Hi just purchased a very nice old rxs100 for my son to use when he turns 17 and also to relive a part of my youth. I had one brand new in 1984 and remember what a great bike I thought it was. I need a few small parts to bring it up to scratch and I am wondering if there's anywhere you can still get original spares from. I also have a 1989 rgv250 and can still get most spares from a suzuki dealer. If anyone can point me in the right direction I'd be very grateful. Cheers Nick.