JimR

Hi Steve, Yamaha bought MBK (motobecane or mobylette as the French company was then called) in the early 80's and produced scooters (Neos/Areox) there and also Yamaha & MBK badged electric cycles .... google Yamaha PAS. So along with the Itallian engine manufacturer I would guess MBK to be a part of Yamaha europe so a search for Yamaha luggage or something of that sort may produce the result you need. Regards Jim

Hmmm, TBH I would look at the bulbs in situ & xref them against the relay you may find swaping the bulbs & relay to a lower wattage (i.e 10w ~ 8w or 21w ~ 8w or 15w ~ 8w) and making sure the charging system is working correctly & the battery is good. Droping down to 8w will give you much brighter lamps (as long as the battery will stand it) but if the battery is no good the lamps will flash too fast as the charging system is supliying too much power to the DC system in order to charge the battery ... knacked battery may need 9v to charge it .. indicators switched on at this point will have 9v applied to the relay which will allow the indicators to flash to fast & too much draw from the battery charge circut. Regards Jim

Hi the Dt kit will do the job bar perhaps the cable length, dependant on where the servo is mounted, The loom on the TZR has the same colours as the DT so connection to the loom may need just a few alterations (I dont know what DT kit you are looking at) in order for it to work. The Valve will not bean issue as you already have the valve sat in your barrel. without fitting the kit. without fitting the kit just cut a groove at 180 degrees to the original (this makes a complete groove across the restrictor) turn the valve open and peg it with the restictor, via the new groove. I guess you have done this and found the power delivery a bit harsh .. like a switch ... on or off ? But to be honest that never happend when the bike was new, so the carb may need some work in order to clear the progression tubes/holes, if done this will give you a bike that is a bit slow off the mark (with no stutters at 5 mph) and ridable and when 6k kicks in a little beast ! Regards Jim

Great ... 14.8v is smack in the middle to a degree 15v should start to warm the wiring up .. not good and sorry about the typo should have read 14.8 & not 13.8 Regards Jim

Hi, just a thought If the tyre was not fitted straight (a section of the beed stuck down in the well of the rim) could cause un even tyre wear not unlike a car with tracking problems. I would guess that all the forks are working correctly and are not bent/out of true (another cause) and the mudguard is bracing the forks (dependant on the bike the tyre is fitted to). Personally I would have not reduced the pressure in the tyres, in fact I would have been inclined to increase the pressure while the bike was stored. I would guess if the tyre found its way back to Conti they would produce some evidence in favour of their product & perhaps citing bad maintanence... So I guess make sure the bike is spot on & replace the tyre with a new one and check the tyre wear, the tyre should show signs of wear at a couple of 100 miles, if the bike is correct and you have now 2 tyres worn oddly Conti would perhaps do something Regards Jim

Hi Mr Alpine, just wondering on which Xj900 you own Diversion or Pre Diversion ? as they do have different tyre pressures but you may need 2.0 bar front & 2.5 bar rear Regards Jim

Hi, ummm so you have fitted a big bore kit ? the running proceedure could depend on the bore/piston clearence a slack bore need very little running in but if too slack the piston will self destruct in no time but Yamaha supplied the following info with 2 stroke moter produced there as the TZR motor is an eyetie (Italian) production the guide lines may be different Yamaha Guide lines read :- 0~300 m Avoid prelonged above half-throtle operation. It is good for the engine if it is allowed to cool about 10 minutes for each hour of operation. It is recomended that during this period the engine not be operated at a constant speed. Vary the speed occasionally. Do not exceed 1/2 throttle. 300 ~ 600 m Avoid prelonged full throttle operation. Avoid cruising speeds in excess of 3/4 throttle vary speeds occasionally. Above 600 m The engine can be operated occasionally at full throttle but becareful of the engine condition and check for noises, etc. End of Guide lines When at the factory in Japan in 1980 each bike was red lined in each gear (up & back down the gearbox) as a final test from the production line so from that I would guess if the clearences are right on the piston/bore and piston ring/bore are correct you can thrash the nuts out of it ... I must stress that this is from Japanese production and not European but I would suggest Minnerilli would have to produce the engine to the same tollerances as the Japs. Remember if the big bore kit was from another manufacturer there is a chance that the tollerances & materials used may not match the O.E.M spec. Regards Jim

Hi Jdh, dont forget the oil light is a level switch & not pressure switch.. if you give the bike loadsa beens up hill the light will come on this is not an engine fault just the oil being pumped around the system and the switch being devoid of oil, just thought I would mention this for the future as if it was a pressure switch this would indicate serious engine damage so as long as you know this may happen don't worry, and of course it has no bearing on the problem you have at the moment. Regards Jim

hmm , dont forget the oil light is level & not pressure ! I guess the neutral light is working, if not the bike may be confused thinking its in gear so you could try making sure the side stand is up & the clutch is pulled in. With the oil light coming on you have power to the switch so the problem will lie further down the wiring if the n light is working .. Sounds like the problem was the VR allowing a high voltage but it may have been the genny which blew the VR out. By disconnecting the VR and riding the bike you could have damaged 1) the genny (but I would doubt it) 2) the battery from the original overcharge and from perhaps flattening it on the 10 miles home. A test to do would be to first off check for a spark, take the plugs out earth them to the head switch the bike on and jump the starter switch, if you get a spark at this point reinstall the plugs and try to start the motor via jumping the starter switch, If it does go you will need a multi meter to check the voltage across the battery (13.8v @ 3k should be good, which should rise no higher than this as the RPM's increase to say 9k,). If this works I would guess you have a nacked starter switch, check for melted wires to it & across the loom check for burn/heat marks as this may indicate a fault within the loom. sorry not to be more help but until you start the fault finding process all I can give you is a collection of things it may be, so perhaps you need to start checking things in a logical order so they can be removed from the problem. Do ur switches first sidestand,clutch, engine kill switch & N light then move down the system. Regards Jim

Hmmm, I'm sorry I cannot see an alternator problem causing a problem with the bike starting ( whatever the tinkering was) if the battery supplies 12DC the bike will run until the battery ,discharge, voltage is less than the voltage needed to supply the ign system. So if the bike runs on battery voltage until flat you may have a charging problem, but if the battery still has some beans left when the motor dies , you may have another problem. Regards Jim

Well perhaps is it air cooled or water cooled 'motor' there could be a difference on how the 'motor' is tuned .. but I would guess its a better bet to px it for the old R1 ! Regards Jim

Hi Tyler, did you buy an MF type battery ? this could cause a problem (the battery has died !). The clicking you hear will be either a flat battery .. not enuff poke supplied to the starter switch or as documented before the start switch itself gone west.... to test the switch just short across the terminals & the starter should spin, if you do this & all the lights go dim & clicks from the switch suspect the battery. If you are sure that the battery is ok (you have tested it in another application) it may be worth looking at the starter motor itself, by shorting the switch you will test the motor, applying the correct current to the starter motor without the switch will confim that the starter motor is fine & the switch is at fault. At this point is the starter motor does not turn the motor over you have 2 remaining options 1) A fault with the starter motor .. brushes and such like 2) if 1 is ok a seized motor I would guess the answer will lie with the preamble or the starter motor and not the engine itself.... unless the motor was well knackered. Regards Jim

Hi DtGordo, we are talking about the big (?) blue dragon ... a Jawa 350 and not the DT50 .. the Jawa has some stout front pipes attached to some odd silencers, in this case I would guess some one in the past has applied some after market exhausts which don't seal as the O.E.M silencers did against the oem front pipes Regards Jim

hmm will it do 88 mph I guess it may if you take ur foot of the gear change pedal .. nor turn it into a kick start !!!! Regards Jim

Hi, between drewpy & I I'm sure that we can get your bike running and you can then ride it like a sea biscuit ??? Regards Jim

Hi, you have one of two problems 1) The Battery is flat/knackered 2) The Fuse is blown Regards Jim

Hi, So how come you didnt get the bike out of second ? a gear change problem or was it a bit fast Regards Jim

Hi OG It was great fun the only problem was too much gas .... and you lost the rear number plate Regards Jim

Hi so has the 'slovak hog' got all its cogs ? or has it been to the Dentist ? Regards Jim

Hi, I wondered if you had found this feature, dunno why Jawa fitted it as the only thing I found to do with it was to pop wheelies ... drop her into first rev the nuts out of it take foot of the gear change lever ... heypresto an odd bike with the front wheel in the air (not so good when the wheel hits the deck as the front forks are well soft. The idea, I guess, was to ensure that the agricultural gear change had the clutch in use as the change happened. At the design time most of the jap bikes could change gear ( when moving without a clutch, in fact I tend not to use the clutch when off the mark as you get much slicker changes) the Jawa g/box would never cope with it so the clever Slovaks produced this system. Other bikes that use the gear change pedal to opperate the clutch are bikes like Yamaha T50/80 & the Honda C50/70/90. Not many other bikes use this system, but just think of the wheelies you can pull !!!! Regards Jim

Hi Joe .... The no spark question .... have u a spark at the leads with the caps & plugs removed ? Is the engine stop switch (r/h handle bar above the start button) in the run position ? If you have no spark at this point. It's time to look at the points (timming & dwell angle) and general wiring for dodgey connections & 'modifications' with in the ignition section Regards Jim

Your just not listening ... fair enuff Regards Jim

Hi W/F A Jawa running well that sounds odd ! but going back to the point in question as the Jawa 350 twin is well old school there is no need to add modern tech to it (back pressure etc) .. the beast will run with no silencers/expansion chambers as well as it it does with them.. sorry to pee on ur bonfire but I sold the Skoda/Jawa bike new and it was good as a £400 bike would do (new that is) I guess your bike is at the end of the production cycle but I would think it would be the same as the good old 70's Jawa twin (motor wise), with later styling and 'body work'. Compared with a DT50 the 350 will seem well powerful try puting that against an RD350B/400 it would get well 'lost' Regards Jim

Hi There, its a good old YL1 and oddly enuff only a 1000 engine numbers from the one I had !! thats cool as we are so many miles apart ! I loved my L1 went well ... sort of 250 brit bike eater and the ladies loved the speed ... the only problem was it was difficult to procreate on as the dam thing kept falling off the stand Regards Jim

No chance of that, the reed valve is after the the carb & before the cylinder so there for the reed opening will have no bearing on air intake to the motor as it lets in the fuel/oil/air before the valve ... The valve is designed to stop gasses being returned to the intake/venturi, which if allowed, would make the engine run differently to how the designer imagined without the reed block installed. To date you have not responded on the other issues with the motor .. the 'black oil' you have leaking is that from the R/h cranck case cover or the centre cases ? If you have mixture being expelled from the centre case the engine is in free fall but I guess you have not looked at the the ignition side of things yet (to discount that) nor have you then followed on to the carb, it must be one of them unless the TZR50 has some odd bits that I don't know about. Regards Jim