nayruf

Hi I have been following this rebuild with some interest, a thought has occurred to me on the question of coolant, have you considered heat transfer fluid for motorcycle cooling systems, a similar product is often used on vintage cars http://www.demon-tweeks.co.uk/motorcycle/coolant/evans-powersports-bike-cool-180-waterless-engine-coolant have never tried it but it could be a useful product. Its just a thought,

Hi Alex Do you mean that on the outside of the carburettor body there is a steel dowel / ball that is the 'throttle slide' guide if so I have never seen that before, is it shown on my first pic just under the 'MIK' logo on the carb? If it is and it will not stay in position and looks are not too important you could mix some 'araldite' glue or similar and put it on the outside of the carb to stop the guide from moving out of position, Or if you are a bit adept with a hammer and a punch, very carefully re-peen some of the aluminium carb body around the ball/dowel to keep it in place, but this is not for the faint hearted as it will be sooooo easy to damage the carb if you try this you would have to have the carb off the bike it would have to be fully stripped and the inside of the body of the carb would need to be well supported to help prevent it from getting squashed, but this would be something I would only try as a bit of a last resort,

Hi As Sacha said if you are using the oil injection system (I recommend keeping the oil pump and not running on pre mixing oil into the petrol) you can use either, just block off the one you don't use as it will allow extra air into the motor and that would cause trouble.

Hi Yes you should beable use a 76 carb on a 75 bike, but there could be differences, My 76 bike has a stub pipe on the inlet tract, this is for the oil pump delivery connection, earlier bikes have a ‘banjo pipe’ connection in the side of the intake tract on the cylinder (jug) see the bad pic below the oil pipe is the one in the middle near the bottom of the intake, in the second picture you can see the old oil feed location in the casting on my bike a later bike its not used, I cannot think of any other differences,

Hi Yeh, start a workshop thread, when you say the revs are high, if by mistake you have put the throttle slide in back to front the bike will rev really high as the slide will be held open, there is a little steel dowel pin in the inside wall of the carburettor body that locates the slide also you can see on the slide there is a little sloped portion that the idle screw pushes on, noting either of these will ensure that the slide is fitted correctly, I have fitted the slide wrong a few times,

Hi I don't think there is a nice way of overhauling the speedometer, check this link out from a previous post

Hi Listening to your you tube clip, maybe it could just be a bit of an air leak, spray the various joints and gasket interface areas with 'wd 40' whilst its running, could even be chuffing out of the spark plug hole if the plug is a bit loose,

Hi Pretty much yes it does, the dash codes mainly apply to 'O'ring seals and this is for any fluid type or even gasses, but you often find that similar can be applied to garter type seals as used in all sorts of places from fork seals to crank case seals, I got a triple lipped garter type seal for my back wheel this was an up grade on the dual lip original seal, the seal supplier was able to measure my original and cross ref its pt number they then supplied the better seal, my experience is mainly with 'O' rings but size conventions exist for most types of seals, a point to note is that even though the seal is made from elastomer it can grip on a moving shaft and will wear the surface, we some times need to apply tough coatings to protect shafts,

Hi After reading this post on ‘O’ rings made me realise that although in engineering we take ‘O’ ring sizing for granted. Others may not know this info, There exist several international standards of ‘O’ ring sizing systems, Ranging from ISO, BSI, API and Aerospace Standards (AS-568), Anyhow because of this standardisation we can use these sizing systems to give any ‘O’ ring we need an AS – 568 size/part code, the trade often refer to the sizes as ‘Dash Codes’, so if you know the Inner Diameter (ID) and the Cross sectional area (CS) you can give pretty much any seal its part, size code, as most of the planet uses the AS-568 system its often best to do a search for a pdf size chart from the net, read up on how the coding system is implemented then apply it to the seal you are looking for, once you know the size code a net search should find suppliers that can provide seals that main dealers charge a fortune for or that are no longer supplied. Once the seal size code is known the most compatible material type is needs to be picked, This can be done by searching on the net for Elastomer compatibility reference charts, this type of search should give you several options of charts to pick from mostly dwnld PDF’s but some interactive searchable links to mainly associated to companies that provide seals and similar equipment, ( Cole Parmer is the one I often pick) although most suppliers will know the best materials for a given liquid and its temperature,

Hi I too have similar, it’s a DT 175C 1g1 model, It is really easy to service, the gearbox on mine I use every day motorcycle gearbox oil, the cables require adjusting and perhaps a bit of lube depending on the cable type, the swing arm has a grease nipple so if there is no play in the swing arm bushes, I just pump some grease through it till clean grease oozes out, the spark plug is a straight fwd swap to a new one the gap only needs setting, the air filter can be cleaned re-oiled and reused, the wheel & steering bearings can all be checked for excessive free play, they can generally be changed at home with fairly basic tools, a small crate under the bash plate will lift the wheels of the ground, I even turn the passenger foot pegs upside down and use car axle stands for the back wheel, The points are a bit fiddly to adjust but again with a set of feeler gauges and a bit of patience they can be adjusted in a few minutes, in fact the only tool that you really need to buy over and above a standard basic mechanics kit is a magneto puller that screws into the left hand thread on hub of the magneto and has a central bolt that screws onto the end of the crank, this puller is an essential piece of kit it does not cost much and will save you loads of strife and save you damaging things, Once the magneto is off the points can be removed the faces can be cleaned and smoothed or replaced, also the points cam and advance mechanism can be lubricated. to change out the condenser a small soldering iron will be needed, I have found that its often worth while to change the points and condenser, so that I can have confidence in their condition, once I have fitted a new or known to be good items I keep dressing and adjusting the points every 300 miles or so, All in all when I service my DT it takes around 1 to 2 hrs to do depending on how thorough the service needs to be. As others have said a manual in PDF form can be purchased from ‘fleabay’ quite cheaply,

Hi to find out the best possible material choices for the tubing, do a google search for 'coleparmer chemical compatibility database' it is a data base that lists amongst other things elastomer materials and their resistance to chemical attack from various chemicals. Buna Nitrile is a good choice as are Fluorocarbon elastomer's aka 'Viton' hopefully this may make it possible to to have a broader choice of tubing suppliers

Hi I think pictures would help unless someone who has already done this to their bike replies. I fitted a braided hose set up on my 900 divi, the kit consisted of two long hoses one longer then the other, to be fitted from the master cylinder to the callipers either side of the wheel, the ends were ‘Banjo’ fittings, the kit came with two short ‘Banjo’ hollow bolts, one double length ‘Banjo’ bolt and 7 thin soft washers, the set up was to fit the long ‘Banjo’ bolt at the master cylinder thought two of the ends of the hoses sandwiching 3 thin soft washers the hoses were routed down each of the fork legs with the longer hose going to the furthest calliper from the master cylinder, I fitted a ‘P’ clip at the mudguard mounts either side to keep them in place allowing slack for the suspension travel, then the final washers and Banjo’ bolts were used to connect the hoses to the callipers, I don’t know if your bike has ‘ABS’ if it does then this might be no help at all, but this is how it fitted on my 900 divi.

Hi Once I have the pump set and adjusted as per the manual I just pull on the oil pump operating cable at the engine casing to open the Pulley and observed the smoke increase as the bike ticks over, I have also once or twice disconnected the oil feed pipe at the carb for a few seconds as the bike is ticking over and seen oil pulsing out of the end, however I don't like doing this for long as the revs increase as the airflow goes up slightly and the motor is obviously not getting oil. do a search for 'dan's motorcycle two stroke autolube' and a search for a PDF called: 'yamaha oil pump rebuild - YDS motorcycle parts' both I found interesting when reading up on my bikes pump aj

Hi You will be better served if you say hello in the new members section, My old Divi had a fuel gauge problem, it turned out to be the pivot bush on the fuel level float sender unit inside the tank was worn, apparently today's fuel does not have as good lubricating qualities as petrol of old, anyhow I changed the sender unit which is easy to do, looking at the old sender I reckon I could of made a replacement bush, but I had already brought a new sender, you could perhaps look at the wires on the sender unit bridge a contact across them making the fuel gauge show full,

Hi There were some changes to the DT 100 over the years, I don't know them all, but some DT 100s, 'Dt 100 C', I think have an exhaust that fits under the tank left to right and some latter DT 100s I think DT 100 G around 1980 ish have an exhaust that is mounted on the right hand side of the bike. I think there are air filter box changes too, the oil tank will be different, and the swing arms may be different, look up a site called 'partzilla', you can check the pt numbers across the years,

Hi Try to do a net search for 'Mikuni VM tuning manual' you should find a link to a PDF from mikuni USA, I found it useful when I set my DT enduro carb up,

Hi I too switched from a 900 divi to a 57 FJR, to try to answer your questions: 1. Gears - The XJ900 has 5 gears and I always feel when doing touring, motorways or distance it just needs a 6th to drop the rev's a little at motorway speeds. Is this the case with the FJR1300 or is the gearing a lot better, My FJR is also 5 gears and it could also do with 6th gear, although the bike is plenty quick enough on the 5 gears at sustained high speeds 6thgear would lower the revs making the bike a bit more relaxed, Parts pricing - The parts for a XJ900 are readily available and fairly cheap, The FJR1300 being a lot newer, more advanced, is there point i should check really carefully when buying as would be expensive fixes. My bike is low milage, but so far I am supprised at just how fast I seem to go through tyres, the front tyre wears at a higher rate than my divi used to, I suppose its just the price of braking such a weighty bike, Handling - As on a test ride, and not knowing the bike too well i am unlikely to go throwing the bike around, but when not touring i ride with the likes of Ninja's 995's GXR and CBR riders. Will it be too much of a bike to consider keeping up. (Although I manage on a divi) I used to ride out with a friend on a 916 duke and could keep up on the Divi unless he got too spirited on the duke, I reckon on the FJR I would struggle a bit although could make up ground on the grunt the bike has comming out of turns, general service - I do most of the minor things to the divi, and like to tweak bits as and when, is the FJR too advanced for an armature to do any work and is it near impossible to access because of the fairing. I have not had the farings off yet, so far I have found that the suspension linkage lubrication that Yam used when the bike was assembled is pretty woeful, I have stripped out the lower linkages and regreased them something that the divi needed too, my only real problem with the FJR is its pretty weighty and does seem to want to use most of the road when taking high speed turns, (probably due to my crap riding) something I never really experienced on the Divi, and when the weather is really hot the FJR seems to vapourise its fuel and can take a few extra prods on the button to fire up, The gbox is clunky when selecting 1st from cold, I generally push the bike in gear with the clutch pulled to free the clutch off for the first start of any journey, also I am not too keen on the panier side box body work attachment covers they look like they wont take much effort to scratch the body work if you use them often, I have to say if Yam did a new upgraded 900 divi I would of just brought another. I live pretty close to Lincoln perhaps if you are in my area some time (Grantham) msg me and I could tag along on a short ride, Aj

http://www.tytrials.co.uk/trailandtrialsuk/prod_387186-Woodruff-Key-Flywheel-Side-DT175.html

Hi When I had my first magneto rotor’d bike, (late 70's 'S' registered) the woodruff key would shear frequently, I had torque’d the nut up as dictated by the manual and the key would still shear. On investigation I realised that the key does not actually transmit drive from the shaft to the rotor, obvious I know but I was young and inexperienced, I am now old and stupid. So because of this the drive is transmitted to the rotor because the rotor is wedged on the taper of the crank shaft stub, similar to a ‘Lathe or pillar Drill ‘Morse taper mounted chuck’ that has a chuck wedged on its taper relying on the tapers to lock together, and has to be removed with a wedge drift of the correct size, to this end I noted that if the woodruff key sat high in its crank shaft location point and contacted with the slot in the magneto before the magneto fully seated on the taper on the shaft, even with the correct torque applied to the nut the key would shear periodically as the rotor skidded around the shaft, I was able to stop this happening, buy making sure the key was sitting low in its location and even dressed the key with a ‘Riffler’ file to achieve this, I also made sure the tapers in the magneto rotor and on the crank stub were scrupulously clean and free from any grit or debris that could prevent the tapers from locking together. Others may say this is a waste I am an arse and you can ignore this and 9 times out of 10 they could be right. But since 1978 to this day I have not had a key shear on my magneto since, Just a point to note, hope it may help,

Hi My DT twin shock, went through the same holed piston saga, I reckon the bike was probably running a bit too lean, I had to change the main brgs the big end small end and obviously a full gasket set, I stripped the motor but entrusted the crank split to a local bike shop who does a lot of DT mx engines for cart racing enthusiasts, I think it cost me £75 for crank strip and con-rod fitting, the rest I sourced for my self, anyhow its all fixed now, I suppose its all part of the fun of running a two stroke, Obviously the piston on the right was the holed one, the one on the left is just a knackered one from a previous rebuild

Hi Just a thought, if you really want to use the centre stand and you find the bike too hard/heavy to lift using the best methods, you could buy a second hand centre stand from a breakers and get a local welders to add a longer lever to it making it easier to lift the bike, I have seen on on ebay recently and I should think fairly adept welder could extend the lever at a reasonable cost, he/she would just have to see the original stand on the bike to ensure the longer lever would not catch anywhere, http://www.ebay.co.uk/itm/YAMAHA-YBR-YBR125-2007-STANDARD-FIT-CENTRE-STAND-GOOD-SOLID-CONDITION-/281103583930

Hi Phil There are a few twinshock DT's here this is mine a later model but basically the same,

I also think it could mean, as Tax cannot be retrospectively purchased and the Tax is not transferable between owners, if you buy a vehicle on the 5th of a month you won’t be able to have valid tax till the end of the month so I assume there will be quite a few untaxed vehicles waiting to be come legit, this is why I think second hand vehicle sales could be affected,

I agree, I think it might stuff up many private secondhand vehicle sales if the VED is not transferable with change of ownership, I can see that second hand cars will become sold at sites or by people who have a premisis where the vehicle can be stored until a new VED has been obtained for the new owner,

https://www.gov.uk/government/news/vehicle-tax-changes Don't know if this is good news or bad. Probably another way of making using the roads harder and more costly,