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About konrad

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  1. konrad

    Electric start

    Information on US website says yes. http://www.trsmotosusa.com/2020_TRS_One_RR.html http://www.trsmotosusa.com/2020_TRS_One_R.html
  2. konrad

    Ring End Gap

    If you don't get a better answer, I'll say that 0.002" is too tight for anything. I'm guessing it may be a misprint and should be 0.020" as the service limit. 0.012" seems roughly right for new rings. At the risk of stating the obvious, the purpose of the end gap is to allow clearance for expansion as the ring gets hot -- you do not want the ends to ever touch. Minimum end gap is a function of bore diameter and operating temperature. New end gap is typically on the order of 0.004" per inch of bore.
  3. I don't know the answer, but you can download a Braktec trials catalog here: http://braktec.com/product/ I'm guessing the caliper looks like this: https://www.splatshop.co.uk/braktec-4-pot-front-brake-calliper-mono-black-red.html Have a look at EBC's FA644X pads: https://www.oreillyauto.com/detail/b/ebc-motorcycle-5876/brake-systems-16456/brake-pads-shoes-16515/brake-pads-12845/a99314144bb6/ebc-brakes-ebc-motorcycle-front-disc-brake-pads/fa644x/6095770
  4. Are you measuring the secondary with or without the resistor cap (which is typicality about 5000 ohms)? Resistance reading don't tell the whole story. https://www.trialscentral.com/forums/topic/70835-montesa-cota-315r-no-spark-issue/ CDI ignition coils are fairly universal - a better way to test the coil is by substituting it into a working bike (almost any single with a CDI).
  5. Good question. Models such as these have pointed me in the right direction in the past and I always learn something from them. If somebody wants to correspond with me about it, message me.
  6. I've been studying the effect the main jet has on part-throttle fueling and learning a lot. Have found an equation for two flow restrictions in series (in this case the main jet and the needle system) and have written a small spreadsheet based on the Dellorto PHBL 26. Is anyone interested in the results? I ask because presenting/explaining them would be a fair amount of effort. I'm also uncertain what the best way to actually present them would be (I know not everyone is as enamored with numbers as I am). Would anyone be interested in working with the spreadsheet? It's in OpenOffice Calc, but I could convert to MS Excel.
  7. The problem is more than merely academic to me. My wife thinks the thing that will eventually cause her to stop competing is repeatedly starting the bike. I compete on a 250 because it's easier to kick.
  8. Then I will defer to your experience in the matter, sir. Trials bikes are weird.
  9. What is the original source of that chart?
  10. I think the best way to make an alternator/starter work is in conjunction with an automatic compression release. But if just a compression release made your 300 as easy to kick as a 125, would you still want an electric starter? Yamaha used a small (3mm?) bleed hole above the exhaust port on the RD400 to make kickstarting easier. The hole really made no noticeable difference otherwise (as the guys who tried plugging them discovered). I investigated drilling a bleed hole in a trials cylinder once, but it would have gone right into the water jacket.
  11. Tell that to the carburetor manufacturers. Here's just one example: http://www.sudco.com/jetting_assistance.html All are similar. I do agree with your statement in that if you install an extremely small main jet, the flow will be limited at part throttle. But for any reasonable size main jet for the application, that does not happen.
  12. The main jet really has no effect until more than 3/4 throttle. Enriching the clip position may help somewhat, but the needle taper itself has more influence at 1/2+ throttle. Cleaning carbon from the head and piston would help if there is an accumulation. Have you tried a higher octane fuel?
  13. I'm not saying it can't be done, but I do see hurdles to overcome. One is the very high static cranking pressure of a big-bore trials bike. The AT1 (and RD200) had small cylinders with low static cranking pressure. The snowmobile application has electronic exhaust valves that are undoubtedly in the high-rpm (low static compression) position during starting. Two is, on a trials bike, there is often little run-time between starts to recharge the battery, and may rule out a super capacitor altogether. As you may know, the GasGas Contact ES uses a conventional starter with a right-angle drive on the flywheel side. You can see KTM's version here: https://www.youtube.com/watch?v=KQTnUxj16nQ
  14. Congratulation on solving the problem! (And thanks for reporting your findings.) I think the simple explanation is that the pickup coil is polarized. The leading edge of the trigger structure (whether a tooth or a hole) needed to generate a positive-going (or negative-going) pulse for the CDI to work properly. The trailing edge would then generate the opposite polarity. It's not uncommon for both of these events to be needed in order to set the timing and sequence of operations inside the CDI. Quite frankly, I'm surprised it made any sparks at all. There has been a lot of innovation in ignition system design over the years -- as much so as engine design, it's just less visible. It ain't called a "black box" for nothing!
  15. I missed this the first time around. That delay is really weird. I guess if I had to throw money at the problem, I'd throw it at the CDI before the stator.
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