yamguru

hiya i wasn't aware there was one do you have a link to it?? Cheers

I am looking for any completed 70/80's restorations to feature in the regular MCN classic section this is a great opportunity to get the classic scene to a mainstream audience and also a good way of recognising the help suppliers and clubs you have used and been a part of pm me on here for more details and lets get you and your creation in the paper

i would go one stage further and say that no OW31's found there way into private hands the numbers made didnt go into double figures and i know where all of them are there was a few YZR750's that did go on to private ownership but this was a further development of the OW31 and miles different in specification the bike that Crosby won daytona on for example now lives in italy but has not been raced since that win the very first 750 (chassis #001) was tested in june 73 and following that the button was pressed to start production for the 1974 season Agostini won daytona ( 200 had to have been built by this time to be eligible) on one that year and privateers were getting bikes soon afterwards 260 bikes were built in 1974 and labelled TZ750A's they were 794cc with the same bore and stroke as the 350's 1975 saw the increase in bore to make 747cc and from there on the engine remained pretty much unchanged for the next four years when production ceased monoshock came in 77 or though harris and spondon were modding twin shockers into monoshock from around mid 74 around 530 bikes were built in total and a similar amount of engines were also supplied seperately

there should be three white wires, all in one block connector, from the charging part of the windings ( not crucial which way these go) a light blue wire also in this connector for the neutral light a black wire which is earth ( rubber mounted engine) on the ignition side of things and feeding the CDI box should be; a white/red wire and a white /green for the pulser coil ( the little one on the outside of the rotor) the a red wire (high speed running coil) a brown wire ( common feed between the two) a green wire (low speed running coil) i can supply resistance readings for these if required but i will need the exact model

two ways to deal with this one either take the clutch cover off and dismantle the clutch to free the plates off or simply bump it off and ride it down a straight bit of road for a few yards or so the clutch will free itself in a short while

98-99= 4XV-21110-00-00 2000-2001= 5JJ-21110-00-00 02-03 = 5PW-21110 04-06= 5VY-2116J-00-00 hope this helps

the spiral design was never as strong as others types the worst being LC front wheels that would crumple in even the lightest crash you can get cast wheels re aligned though

thats what its based on US parts

most yamaha dealers and mechanics know how to translate part numbers any way yamaha use the same numbers and codes for the same parts so most are instantly recognisable its not rocket science

watch out though its for the US based models only

is the air box fitted correctly they can be tricky and any leaks will screw up the high rev fuelling

good to hear it starts now thank god it was just a carb problem track down a product called power pill or similar and run this through your carbs it sounds as if the needle tubes or pilot jets are a little gummed up

i dont want to worry you but this is starting to sounds like an ignition fault to me im no expert ( 28 years as a yam tech) so don't listen too hard but id get the timing checked before you go much further

i would get the compression tested and aim for the head gasket in that case

there shouldnt be any perceivable play in teh B/end bearing so it should be replaced if it does fail they usually take the piston and or the barrel with them so its your choice but i know what i would do as for the water most likely it is the water pump seal

the carbs on the TDM cant work properly with the air box off so thats mainly why they were spitting back have you tried using some jump leads to get a sustained voltage while you press the button when it tried to start what happened next ie why didnt it go and what had the biggest effect

sounds to me like the sprocket nut has come adrift not many mechanics today will know they need around 60ft lbs of torque the tighten them and also the lock washer has to go on a certain way if the sprocket comes loose then it also stops sealing the gearbox oil and it will come out this may well have punched through a casing if the gear box has failed then they usually lock up a primary gear or clutch centre nut could have come adrift to but check the sprocket first you can safely run the engine without gearbox oil for a short time

thats still a lot of oil to be passing thorugh a valve seal!! is the oil burning in the engine ie are the plugs blabk or is it just getting into the zirts and getting hot?? id be tempted to get the compression checked and also the air filter box as it is possible for the crank case breater to be heavily venting and the oil to be passing straight through the 2/3 carbs is this bike an import? some yank models have exhaust feeds from the cam box into the exhaust fia reed valves etc could worth checking out as thta would pu oil stright into the exhaust add a bit more info and ill get stuck in

sounds like you have a dykes ring in there the L fits in the top groove of the piston and makes it so the ring forms part of the piston crown for a higher compression the dykes ring has a lower friction contact with the bore as it relies upon gas pressure to force it out

these carbs can be buggers to get fuel though if they have been stood go for the dropping gas down the plug hole option or find some other way to prime the inlets with neat gas via a vacuum pipe etc

ask Ron Dennis!!! he has certainly tested it beyond its original design brief ive heard great things about it but never used it personally it was the first fully synth and they have spent a bundle on it since so i guess it must be up there it certainly isn't a shell base oil with additives put in and rebranded!!!

Motul is about the only brand of lubricant that exceeds by a long way the specifications laid down by engine makers etc that means that temperature wise it can be run a ot hotter before it ashes in the case of two strokes or breaks down in the case of a four strokes i have seen this first hand i my own race engines that had they been running another brand would not have made it over the line after a mechanical failure etc i know for a fact that a lot of teams run Motul oil and run other peoples stickers for financial reasons it is very good stuff so why run anything less than the very best the other oils i mention as liking have also been tested extensively by both myself and race teams i have worked with as well as part of many magazine articles etc the man on the street is attracted by fancy advertising, after all thats why the companies spend so much on it, and in the case of silkolene the in store stuff is very compelling but look around and see how many race teams are using the stuff when compared with the huge market share they claim to have in the UK?

just a personal thing really it is obviously good enough or else they would be out of business but to me it is nothing special just good oil not great pro 4 plus is a fairly high performer but nothing as good as motul or shells race oils silkolenes highest price synthetic two stroke oil is exactly the same as their scooter oil which is half the price it is just in a different bottle aimed at a lower spending market!!!

to be honest i have never been a big fan of silkolene having tested it extensively on my own road and race bikes and also building engines for many people over the years its ok but thats about it there are better lubes around for high spec 4 strokes you cant beat motul with shell and castrol running a close second two strokes and the best premix i have ever seen has been morris fully synthetic its awesome stuff with motul 800v, rock oil and shell advance very high up there ike i say just personal opininion based upon long distance road bikes, dyno runs and race winning experience i might put silkolene on my chain or in my forks but never in the expensive bit!!

the FZ600 has the same clutch plates etc as the 78 XS500 and 92-97 spec XJ600 not the XZ550