drewpy

try http://www.aircooledrdclub.co.uk/forum/ and do a search

depends on what tyres you have, manufacturers recommend different psi to standard

the pilot system affects the lower rev range to 4k 'ish and the mains take over. The galleries in the carbs are very small and even after i cleaned them they were still blocked. that is why i ended up sending them away to be cleaned. the reving you encounter is a weak mixture in the pilot system, but any tweaking of the screw will not overcome the reving. BTW its 1.5 turns from the bottom. Another fault i have found is the pilot screws snapping off at the bottom due to wear of the brass and hamfisted tighteneing (an interference fit into a conical seat) you can check by completely removing the pilot screws and they should have a really fine needle on the end, if they are "dumpy" ie rounded then the end has snapped off, this has happened on both sets of carbs i have had! the float height is very important:- yamaha say 26.6 +/- 2.5mm using a venier caliper, measure the distance of float arm from the top of the float chamber gasket seat (no gasket) to the top of the float. (the float should be resting on, but not depressing the spring loaded inlet needle) bend the tang to achieve level amont both right and left floats have to read the same. Drewpy

genuine exhausts are almost unobtainable now, but sito are available as well as motad 2 in 1's and MAC in usa. Need to check out cmsl.com for parts and speed sport in usa! as I am not too sure regarding the 360 (might be able to use 400 pistons etc. best tyres are BT45's, the rd boys swear by them. drewpy

sounds like a blockage, do you use an inline petrol filter?

far as i know its to supply enough petrol for the carbs and the way the tank sits on the frame!

I don't recommend soaking in solvent as there are rubber bits in the choke mechanism. what you need to do is get them vapour blasted ( for looks) and then ultrasonic cleaned. I use jrs in Uk but you will have to do a google search if your in the USA. these will come out ultra clean and JRS even replaced the parts of the carb with my keyster kit and built it up for me! approx £100 for ultrasonic clean.

sounds like the swing arm bushes have gone, you can check by the sideways play on the swingarm 1mm max (is on my xs400) the electrics on those bike had a reputation along with the cam chain. I agree that they are great looking bikes, the 850 was the updated 750 with all the niggles sorted. have a trail through the old forum via the search system as I'm sure that someone has asked the same question. BTW check the middle gear box oil as that gets forgotten at service times!!

If the vaccum gauges do flutter, there is a knurled knob on the pipe which needs tightening up till the fluttering stops. this acts as a damper due to the engine characteristics and is normal on all bikes. checking my manual, the carbs are the same as the 400 but have different sized jets, so you need to ask them for a 360 kit. the 360 has; 135 mains, 0.6 air jet, 4FP21-3 jet needle, X-6 needle jet, needle position 3, pilot jet 17.5, starter jet 40. air screw 1 to 1.5 turns out from stop. send them an email, as they have tons of stock. if they don't have any try NRP in Manchester UK!

Those are the carb kits, in fact the exact same ones I bought. Don't forget you need two! The valves are really easy, just use your manual to set the crank to the timing marks and 10mm spanner and feeler gauge. rtv on the inlets is not a good idea, use a gasket and check rubbers for cracks/splits

WOW some text 1) Sounds like air is getting into the inlet side of the bike. Spray some wd40 around inlets and listen for any engine revs which would iindicate a leak there 2) you need to get a keyster carb kit and replace everything with the kit 3) tune the bike by setting the valves, points gap, timing and finally balance the carbs. If you get the vaccum guages there will be instructions in there. you need to find a way of supplying fuel with the tank off the bike and you use the stubs on the inlet rubbers as vaccum take-off. hope this helps

I assume your talking about the 2A2 engine, as there was a later dohc engine which won't fit. the xs400 will slot straight in and is in fact lighter than the 250 (bigger bores I assume) you can't just overbore as the valves are a lot smaller and uses a different carb 32mm-250 34mm-400. I think even getting a 400 barrel onto a 250 bottom end could cause the liner to foul the crankcase mouths (not tried it, but i'm guessing) I bought a 400 engine off ebay for £50 and carbs for £20, then you need the rubber between each side of the carbs for the bigger mouths. Well worth the hassle though as mine motors up to 85 and great on the twisties. a custom model will fit as its only got a rounded barrel as opposed to a squared off one. Be careful of the 12n model as they have "rear sets" which If yours hasn't then you need to figure this into your equation. BTW loads of stuff in germany, but be carefull with carbs and camshafts as they have restricted (27bp) engines drewpy

I'm thinking; Flying time and CAT B write off

Go for it, if you like the bike its gotta be worth it. over 15 years old is considered a classic nowerdays!!

Have you tried ultrasonic cleaning? I used JRS and cost £100 for a pair to clean.

quickens the steering at the expense of high speed stability

its the union flag not union jack.

don't fortget to break the seal first on the rim. I run my car over the tire slightly and you can hear it crack. otherwise you can't get a lever in.

My understanding is that emulsion tubes are the tubes which the needle runs in, Jets are screwed in at the end of the tubes

sounds like timing to me, I put my thumb over spark hole to get feel for the compression then I know the timing marks will be tdc.

yamaha only made xs240, xs360 xs400 xs500 xs650 (twins) xs750 xs850 (triples) and xs1100 (fours). no such thing as an xs600 need to go back and find out which it actually is. may be get the engine number, number of cylinders would also help.

no problem

Get yourself a manual and read it. Haynes should do one for your bike and it tells you what needs doing at what intervals and how its done. That's how I learned.

Smartarse