tony283

A very annoying and frustrating experience but often a cheap fix. With older machines there are often a lot of "shade tree mechanic's" work which take time to rectify. Most problems of this kind are invariably carb related, or a problem in the inlet tract. I have had a couple of bikes in where "shade tree" has used the dreaded SILICONE on the faces of the carb mounting or on the barrel itself. This stuff will heat up and melt and then when you are downhill on idle it will blow back on the leading edge of the slide and then hold the slide in that position until it cools. The other likely problem is a very small deposit of corrosion on the fuel inlet. As the engine starts to run out of fuel it sucks in more air and the engine speeds up, this will then vibrate the sticking float mechanism allowing some more fuel in and the cycle continues. First I would use the soapy water technique and look for the tell tale bubbles, head, base of barrel, and all of the inlet joints. Next take the carb off and remove the float bowl and then holding upright see if the fuel inlet opens when you move the float up and down. If it sticks at all give the plunger a light polish with a fine emery. Check the slide for smoothness and clean well. Blow through ALL orifices in the carb and check all the inlet joints for that dreaded silicone...... last resort change the carb. Tony

The easy to see differences between the TY175 and TY125 are as follows. All TY 175's have frame numbers starting with 525, stamped on the right side of the headstock. The TY 125 starts with 539. The TY125 usually has a steering lock on the left side of the headstock. The frames are slightly different and on the TY175 the sidestand attaches to the right side of the swinging arm. The TY125 has the sidestand on a bracket below the left footpeg. On the TY 125 engine the number is often JUST 539 with no other numbers. The carbs are different but just about everything else is interchangeable. Tony

Yes, like most TC threads this has wandered way off the original topic! which I believe was the appalling treatment of a particular AHRMA volunteer who, as usual did a fine job but was discarded on the the drop of a hat...... remember the Woody Graves treatment? While most of us have tremendous respect for the Trustees these last 2 incidents leave us all speechless, let alone the ridiculous opposition to the inclusion of a modern twinshock class. Should AHRMA wish to hold Trials events reminisecent of the 50's 60's and 70's then perhaps they should revert to a single line section with all classes attempting the same section. There of course will be big differences in the scores depending on class and ability but that WAS THE WAY IT WAS. ITSA does try to capture some of this idea but isolates sections to varying classes or ability levels so therefore never gives a first timer or Novice a true idea as to how he or she performed relative to an accredited Expert on the same line. Comments regarding the "loop" are in my opinion worthless as are comments on "AHRMA 4 line riders" as in National Competition you can either ride the bike or not, and if the loop is too difficult to ride or the sections are outside your current ability then.... don't whine or complain, get out there and practice or take up another sport. Tony

Alan See my "blog" under "77 gets her 2008 makeover" this goes through how to fit the footrests and how to fit them if you are using a 74 frame that is not a CAT model. Tony

You might find some of the information on Yamahas on my "blog" of interest. Scroll down to the December 2007 articles and you will find 3 articles on building "Baby Yams". In January there are a series of "How to" articles which covers the Fork oil seals on the Yam, a very simple job if you follow the guide. If there is no power check all electrics and carburation before looking at the piston. Good luck. Tony

Damage usually happens when the clutch has been incorrectly assembled and the washer has been left out! On reassembly make sure the inner and outer baskets are free to rotate and not locked together. When fitting the plates make sure the offset "nipple" goes in every 60 degrees, so the plates will be in the 12,2,4 o'clock positions etc. Also check that someone has not left the ball bearing out that fits between the 2 clutch push rods. Apply ATF to both steel and fiber plates during assembly. Finally check the screw on the flywheel side is engaging in the the clutch actuating shaft (you will see it lift a little as you adjust). Finally fill the case with ATF and try it. If the bike has sat for a long time the plates may be DRY and the clutch will not work until the engine and oil are hot, this could take up to 1 hour before it works correctly. Keep working the clutch to get the oil between the plates and eventually it will work normally! Tony

Dave, Very sad and unusual. However, when your time comes what a pleasant way to go. Numbers for this event have been increasing over the years and this year the New Mexico Club had their modern riders enjoying our sections and a couple of "Modern Only" sections to show their skills. They still lost quite a few marks on our AHRMA sections using no-stop rules. Tony

Yet another report from the AHRMA Vintage Trials at Sandia New Mexico where Mick Andrews was the guest of honour, lots of pictures and several of Mick on my blog. Tony

If it is a Trials Cub and not a Mountain Cub and properly set up for trials you could be paying a lot more than the asking price. My Cub, if put on the open market would cost between $8-10,000. Depending on what, if anything, has been done you might need to spend another $2000 to bring it up to a good riding spec. Throw up some pictures and we can tell you what it might need. Tony

Full report and pictures of the Ahrma Vintage Trials, Two days in Tooele Day 2, is now up on my "blog". A great new venue above Miller Motorsports Park in Utah. Tony

3 days after the Ahrma Trials Casper Spectacular in Wy the venue moved to UT. The full report and pictures of this NEW venue is on my "blog" under "Two Days in Tooele Ahrma Vintage Trials Day 1". Tony

I have used KREEM on two alloy tank with great success. Tony

Day 3 of the AHRMA Casper Spectacular is now up on my "blog" for those following this rivetting sequel of "Old men in a parade on old machines"...... well we did have some youngsters too! Tony

Greeves, yes, something there for all tastes. Day 3 was even wetter and then 2 more trials at Salt Lake before coming over to Sandia and nearly a week with MICK ANDREWS..... more reports coming soon. Tony

Yet more from the AHRMA 3 day event in Casper, full report and pictures on my "blog" of Day 2. Full results are on www.ahrma.org Tony

For those of you who like vintage trials the AHRMA 3 day spectacular (Day 1) at Casper Wy is now on my blog and the results of all three days are on the Ahrma Web site. Day 2 will be up soon with all the pictures and Day 3 at Casper will be published on Tuesday. Tony

I use Sidi boots for all aspects of motorcycling, touring/road, track, cycling and have 2 pairs for trials. Sidi has always made an excellent boot for trials but like most modern day boots they are not fully waterproof. Tony

Bill, The seat you are looking for is the one fitted to the CAT model (1974) which had a full length seat, forward footrests and a longer rear brake pedal. You will see them on the Bay from time to time. Try looking worldwide on e bay under Yamaha TY. Tony

Frenchie, As I said 290 was the "benchmark" for starting, pilot jet stays the same. In order to evaluate if the jetting is correct take the cleaner off and then with the dead engine mark a datum on your twistgrip body and the twistgrip rubber with an easy to see color like white. As you open the throttle and can see the slide move from idle mark the TG at 1/4 then 1/2, 3/4 and full. Remember where the problem, if any, occurs then take action. As an "idiots guide" closed to 1/4 = pilot and airscrew. 1/4 to 3/4= slide + needle. WFO= main Good luck, when you get it right you WILL be thrilled! Tony

Frenchie, You say you have a Mikuni and when I rebuilt a Majesty motor using the whole "kit and koboodle" I put a new Mikuni VM26 on and rather like yours it would not run smoothly. After asking the questions with Craig the correct jetting for the Mikuni is 35 pilot and 290 Main. Yes, thats right TWO NINETY it is not a typo. After fitting that size the performance was spot on with no other changes required. As a general rule with the Mikuni, which I also use on my 1960 Royal Enfield Bullet, for 2 stroke you need to INCREASE main jet size with increasing cc's and with 4 strokes DECREASE. Tony

It would seem the proposal was rejected again! The article that I wrote in my blog "That Twinshock Class", was I believe, submitted as the basis of the reasoning for the "New Class". Although we have not heard why it was rejected, YET AGAIN, it would seem that SOME think it would make Vintage sections HARDER and require another "SUPER LINE" to cater for these machines. That was not the intention of the proposal which was purely and simply to include the last of the twinshock machines who currently have NO National Championship and nowhere to ride and are being treated like illegal immigrants. With the high costs of fuel and travel the extra entries would swell the numbers at both regional and national events. The riders who do compete in our events either riding "Those Twinshocks" or modern "Monoshocks" have no complaints about riding "NO Stop Rules" and using either the 1 (Expert) 2 (Int) or 3 (Nov) lines depending on their ability. There was never a question or suggestion that priceless pieces of trialing heritage from the 50's and 60's would be asked to take on sections that were damaging to both rider and machine or that they would ever be in direct competition with the newer machines. You simply maintain the course layout and lines as they currently are and let the newer machines, ALL twinshocks post 1979 which included the Hondas, ride for a National Championship using 1,2 and 3 lines depending on their ability levels. one day, one day....... Tony

Craig, Hit Blog, then scroll down the left side until you come to Archives, go to Feb 2008 (11 articles) scroll through those and you will find "How to Wheel bearings" Tony

We are trying! I recently wrote an atricle on the merits of "That Twinshock Class" I believe it was submitted today with all the other proposals that were on the agenda.... here's hoping. On my blog under "That Twinshock Class" Tony

There is a whole recent thread in the Mechanical Section. If you go to my "blog" scroll down to the Feb articles then see "How to, Wheel Bearings" you can follow the step by step guide with a lot of pictures to help. Tony

This is a thorny topic, with perhaps some form of personal interests from various factions. It is nontheless being proposed (yet again) at the AHRMA meeting this weekend at Mid Ohio. From a personal point of view, with rising costs this would swell the ranks of entries and not alter any of the current classes or Championships. I hope for the sake of the sport that the decision goes in the "memberships" favor. Tony