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Cynic

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Posts posted by Cynic

  1. The gianelli pipes were always regarded as a better pipe that gave better mid range at the expense of a little bit of top end power. 

    Microns on the other hand gave you every ounce of top end go but if your engine was not 100%... They got a bit of a rep as engine killers because of it. Not fair really, not a new thing kids blaming others eh? 

    All I know about the actual servos for certain is they are very reliable and some have more wires than others. But yes if you have a 4dl the safest route is all 4dl parts. 

     

  2. 2 hours ago, What_a_teezer said:

    1 Ok i seem to have found a fairly well priced full athena gasket set, this might be a stupid question but if it turns out the engine we're building is screwed can i re-use the gaskets for the top end when i re-fit a rebored barrel?

     

    2 The zeeltronic stuff looks great, im assuming since it supports dt125's it also supports the tzr125? Because it doesnt mention compatibility with the tzr125 specifically. 

    3  I'm guessing what you mean with the ypvs stuff is that if i can find a 2rk/rh/rm etc etc valve and box it should work just fine but if i use the later ones for 4dl etc etc id need a 4dl cdi unit too? Wondering if the cdi unit for the 4dl would work on my 2rk...

    OR i could some zeeltronic stuff but the site kind of confuses me, if their stuff is even compatible with the 2rk tzr125 do you know what products i would need to do what i want and how much the parts would be? 

    Thanks again for the reply!

    1 I wouldn't. 

    2 Best to speak to them. From the tdr forums I use the zeeltronics units are the goto upgrade as cdi's for TDR's and TZR'S are getting harder to find and more expensive not to mention guaranteeing its working. 

    3 Yes. The earlier bikes have different cdi's that won't swap. Whatever bike you have will dictate the cdi you use. Often the cdi needs the corresponding flywheel and mag combination too so beware of what your changing and why. You could end up chasing down very rare parts. That's why the zeeltronics is such a tempting option. 

    • Like 2
  3. They are 2 different systems, the servos may be the same, they actually use the servos in tdr250, the rd's all the way up to 500 as well as the vmax believe it or not.

    As to the control, they are 2 different systems, you either have the cdi and the control box that lives in the tail (early) or the later unit where it is all in the cdi, shooters choice on that one, or, junk the whole sorry unreliable mess and upgrade to a zeeltronic ZEELTRONIC - HOME unit that controls ignition and allows you to set up the powervalve to your preference.

    As to the bigbore, yes an athena big bore makes these into serious 100+mph motorcycles but the gearbox cannot handle the torque, lacking thrust bearings and positive lubrication so it dies. Considering how good and well rounded a sweet tzr motor is you don't need a bigbore.

    One thing that is utterly unescapable on yam liquid cooled 2 strokes, genuine or athena head gaskets ONLY, anything else WILL fail.

    • Like 2
  4. Agree with the above, also.

    Being of a suitable vintage myself i was one of the spotty yobs getting their hands on these at 17 , well there were a few earlier RDZ125s that had powervalve motors about that we cut our teeth on. Much as many folk went out chasing units to power up the servo, the slightly more budget option, better than just opening the valve as without the servo drive it self closes over a few days was far simpler and cheaper.

    We used to get hold of a lhs powervalve assembly from a 350 (10 a penny at the time) and then use a choke cable from a car, anything works, cortinas and escorts at the time as they were in the breakers but you get my drift. Fit that to the bars somehow, bingo, adjustable power. You will need either 2 cables or a locking choke cable and a return spring.

    You do need to use a de restricted exhaust and rejet the carb to full power spec or you will destroy the piston (if you need to ask...) 

  5. That may well have been a very expensive mistake, electrics are quite often polarity sensitive. 

    I made the same mistake on our caravan and had to replace the tv and the electrical circuit board in the fridge. Five hundred quidsworth for the sake of not checking.

    • Haha 1
  6. On 7/2/2021 at 9:16 PM, blackhat250 said:

    Yeh " i hated my ride on a duke 990, and ducati Hypostrada,  vibration,,-  to much engine braking,  after being on 2 stokes  ,,yuk,,,

    Although " i rode a 650  Vstrom, and it was smooth ,,

    As a 2 stroke man john you should ride a propperly sorted vmax, crazy. Needs to be a good one though, lot more posers than do ers out there.

    • Like 1
  7. You have gone from peak torque/peak revs to peak torque no revs.

    You need to watch the taco for a bit, revving a v twin hard will just send your fingers numb. Peak power is around 8 and peak torque around 7k rpm so in theory your sweet spot for gear changing will be around 7 to 8k.

    Your ears will argue with you because they are used to 20 valves and 4 pistons rattling around (figuratively they do make noise). Now you have 8 valves and 2 pistons so half the noise and exhaust note. Your head will be telling you to change at ? probably 16k. Not being sarky your waiting for the normal resonance of the ace at maybe 8 or 9k if your pushing.

    Dont worry about big handfuls of low rpm throttle either its where a v twin thrives, from as low as 3 k wang the throttle open and she will drive, the chunder ace would likely bog till it gets its stride. 

     

    Short answer you need to turn your riding upside down, low rpm drive is the key. Your all finished and ready to have a cuppa before the ace would be getting on the cam properly.

     

    And, i have seen it first hand, those v twin suzuki's are a looooong way from slow, once you sus the riding style you will rip the commute apart.

    • Thanks 1
  8. Ugly mess to sort out. Dont know a great deal about these little bikes myself. Deliberately bought a carb'd bike for my daughter because i knew how to fix it.

    I know that doesent help your situation, i recall hearing that the Fi bikes have different cam timing and compression ratio's to get the best from the precise nature of the Fi so you could well be flogging a dead horse.

    Your safest and most guaranteed option would be to pick up a cat c or similar that you can tear apart for the engine and knowing you will have all the aux parts you need. 

    Would love to tell you more but don't know, Fi is a blackhole i have never bothered with. 

  9. Providing i can get the time off due to the now critical hgv driver shortage, im up for it, bike is far better this year too. 

    Keilder is a trek, looking at 5hrs min if i go the straightest fastest route stopping for nothing but fuel. 

     

     

  10. Was there anything showing on the plugs, excessively wet or black. Ig is easier to check than carbs but ultimately it sounds like you need to give the carbs a good clean. Your coming off choke at a mile or so as the engine gets up to temp and as she wants a leaner mixture it sounds like she isnt getting it and chokes out.

  11. It's got ypvs in dirty great letters on a fitting on the right hand side of the engine. 

    If you have a learner legal (haha) model it may just have what looks like a bolt sticking out of the rhs of the barrel. 

    Either way Google mk1 and mk 3 rd125lc. The mk3 had ypvs, the mk1 didn't. Look at the barrels on the engine. The difference is obvious. 

    • Like 1
  12. I cannot find tx500 stuff, but its apparently pretty much early xs500 so i was looking at the 75 xs500 which looks to have the same kickstart mech as most yams running on the clutch basket ring gear. Cannot find anything to confirm that though, could be a longer shaft running on one of the gearbox idlers maybe but that seems a lot of hassle

    The starter motor runs a chain to a starter clutch that turns the crank, looks identical to my vmax.

    Spent far too long wondering about it now. 

  13. 2 hours ago, drewpy said:

    If its like the xs400/250 you need the clutch engaged to turn the engine over. If I pull in the clutch I get no drive to the engine

    Ah so the starter runs through the gearbox. Schematics were a bit vague. Showed the kicker and the starter separately. 

    Could be starter related then? 

  14. Half a turn and stops? So what happens if you put it in gear and turn the rear wheel. With the clutch fully stripped as that centre should spin freely in neutral. 

    Also, i dont get how messing with the clutch affects the kick start, the crank and clutch basket are constant mesh, the kickstart drives the outer ring of the basket. You could take the clutch pressure plate, friction and steel plates out entirely and she would still start on the kicker.

  15. On 4/10/2021 at 8:05 PM, Meem said:

    The test drive wont be happening this weekend because of the terrible weather in germany right now.

     

    Spark plug color is a strong blue one. Cant be the problem i guess.

    On thing that came to my mind: It could also be the ignition switch. There is a small spot where the bike is running terrible if you put the key in that position.

     

    Im gonna report back if the weather gets better and i made a test drive.

    That made me chuckle, the 'plug colour' does not actually mean the spark, although its nice to know its a strong blue spark. The plug colour check is actually referring to the electrode on the plug its self.

    White deposits and red specs on the electrode point to lean mixture and/or bag ignition timing. Ideally a light coffee brown is the ideal with black and sooty or black and oily being bad options obviously.

    Good news is that 100cc bikes are generally ridden hard (not a lot else to do with 10hp) so a plug chop (checking colour) is quite a good guide to engine running.

    It does throw the possible issue onto the carb, if the carb needs cleaning and some gunk has got somewhere it should not?

  16. 16 hours ago, Jc390 said:

    I have a 1974 TX500A as the title says, and the clutch wont disengage. It happened while riding a few years ago. Shifted to first at a light with the lever pulled and it stalled. Ever since that day the clutch wont disengage the tranny. Have inspected the plates and measured everything seems to be in spec. The basket moves upon pulling the lever, however when its adjusted to allow that to happen, the kick start wont engage the motor. I have alot of car and small engine experience, but little with these old wet clutch's. Have put everything together according to the yamaha service manual for the bike and still wont disengage. The basket cover of the clutch separates from the plates, but have not been able to see if they separate when running. Basket does have some marks from plates, but nothing major and sanded down and small ledges it did have. Have two bikes, may swap this top end onto the other bottom end, but would like to figure this out. Any help would be greatly appreciated

    So if you take the plain and friction plates out of the clutch does the inner and outer basket move ok, the outer should move with the crank, the inner should spin freely in neutral and you should be able to drive it turning the rear wheel at different speeds depending on gear.

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