jse

That's a good resource. The 96' takes the ST950220 seal which is an RSC 38-48-10 double lip type. I just pulled one out of my parts box to check it against the manual. Jon

The time is now. Jon

I'd try adjusting the carb before doing anything else (always start with the simple and inexpensive things first). Engine warm in neutral, quickly open and close the throttle, each time adjusting the mixture screw 1/4 turn (the screw to the left of the knurled screw in the middle of the carb body) in or out until you get the best RPM pickup or throttle response. You can start by going in or out with the mixture screw, the engine will tell you when you need to go the other way by bogging. Then, with bike in gear and clutch lever held normally in (usually one finger to knuckles of hand), adjust the idle speed (the screw in center of carb body) to where you like it. If the bike continues to lurch, I'd look for an air leak, usually the intake manifold gaskets area to start. The manifold is commonly overtightened and bows out the flexible manifold in between the bolt holes. Jon

If it's a 96' model, the VIN number (front of the frame in between the fork clamps) should start with "VTRGG 2596.........". Jon

70 or 80 to 1 is a little leaner than the factory recommendation but that's what I use and I don't know of anyone who has had a problem related to that premix ratio. The finer filtering inline units are a little more insurance from grit in the carb. The petcock and disc filters on the carb are fairly large pore. The pilot jet often has an opening of less than .014"/.35mm so it doesn't take much to clog it up. Jon

Not ugly, just "mature".......... The video of the Indy race with Roberts on the TZ is on a rare Peter Starr film "Take It To The Limit", which came out after On Any Sunday, and also includes Debbie Evans doing her famous head stand on her TY175 and a nice interview and videos of Mick Andrews (Russ Collin's ride on the twin supercharged Honda engined Sorcerer drag bike is cool too). I'm lucky enough to have a copy of Starr's film and watch it often. As I remember, the TZ was introduced in 1974, first as a 700 and then a 750. I've only worked on a couple and they are a brutal, vibrating bindle of instant horsepower only really happy at full chat. I can only think of one rider, Roberts, that could have handled it at that time. I think Kenny was from a little town called Oakdale, up out of the central valley in California and had done some rodeo prior to full time bikes and I'm sure his old skill set helped him handle the TZ. The RR model runs a "dry" clutch and you'll notice the special A&A cover over the basket. Jon

I'll vouch for Mark, this is true. When I train new observers, I advise them to study their section carefully and try to choose a place where they will be able to see where they think most of the dabs will occur or where a specific problem area is. Stay in that spot during the first loop of riders going through and not change your position, if possible, untill the start of the second loop and only score infractions you actually observe to occur. This way you will be as fair as possible to all the riders. Sometimes you will need to change your point of observation during the loop but try to be consistant. I take the new club riders out the first couple of events and show them how to walk a section and check other riders in our group among other things. One of the "hooks" I use to get new observers is that to really learn how to "read" a section, a couple of the best ways are to (1) help set up a section and (2) act as an observer. The feedback I get is that the riders learn more by setting up and observing than they ever did just riding. Jon

What premix ratio are you running? Your pop-pop-pop may have a cause other than premix ratio. Generally I like to clean the carb every 6 months or so just to make sure everything is o.k. I run another inline fuel filter that is cone shaped and used sintered bronze and it seems to catch the odd pieces of grit that the screens in the carb and petcock don't get. I also flush out my premix fuel can every few months. You'd be surprized at what collects at the bottom of oft-used fuel cans. Most of us have ones we've used for years and sediment will collect at the bottom, especially if you use pump fuel. I use straight race fuel in my Pro for reasons specific to my engine/exhaust system but one by-product is that race fuel usually does not have storage tank sedimant in it that pump fuel has. Jon

I've had Mark do several four S**T rides in my sections and you have no idea how confusing THAT is to score....... I've never really had any problems scoring with club Trials, very rarely with National Trials and a time or two with WTC rounds. It seems that the more money that is involved, the more emotions (and investment in the outcome) run high. I agree with John, bend over backwards to be accurate and fair, but stand by your final decision, it's worked for me for over 30 years. Jon

I'd reccommend cleaning the bike and then take the carb off, you are a lot less likely to run into problems later on. Sometimes just cracking the floatbowl main jet bolt loose a little to let the fuel drain will lead to less water and grit buildup in the bowl. Easily done (fuel into a drain pan, cold engine and outside the garage) and only take a minute or so. Jon

You'll need to take it off. Two V-blocks and a press is the best way but you can use two 2X4's as the V-blocks and a third short 2X4 to pound the bend straight with a heavy hammer. The 2X4 on the bend will not cause a flat spot like a hammer blow would and it spreads the force out a little on the spot to avoid kinks. Starting the bike while the kickstand is down is a very common cause of bent kickstands. They are only designed to hold the bike up and any more weight on the light components will bend them quickly. Jon

Slight engine rattle in neutral is normal if it mostly goes away when clutch lever pulled in (my guess is the "fingers" slightly loose on the pillars). Falling over is not normal and may mean the kickstand has been bent. Ask your mechanic to look at it. Jon

Geez, Mark, you're getting old like me, where temperature takes on much more importance in our functioning. Ya know what? I think we're turning into snakes, so now they probably won't allow us on planes. Heck, with no air travel, we'll have to run everywhere, like the Tarahumaras............. Jon

If the oil level is too low, that could be the problem. Sometimes the cartridge is not bled properly which will result in a too-low oil level after riding the bike a short time and loss of rebound damping. A low oil level affects the rebound damping much more than the compression damping as the piston (which houses the damping assembly) travels down into the oil under compression and up out of the oil under rebound. Two other possibilities are that the damper rod (the rod that goes into the cartridge and the top attaches to the cap on the upper fork leg) is not screwed far enough into the top cap (unusual, but has happened) or, more likely, the "top out" spring (a small spring above the cartridge piston inside the cartridge) has broken. I've not had the 2010 forks apart yet so I'm not familiar with any potential problem areas and these are general possibilities. Unusual for a brand new set of forks to have a problem yet another possibility is that this is a characteristic of this particular fork (I would be surprized if that were the case, however). Jon

NGK BPR5EIX set to .024" Jon

Oil level is always more accurate than oil volume when servicing forks. Oil level is measured with: (1) the upper fork tube collapsed into the lower leg. (2) the internal cartridge completely bled of any air. (3) the spring removed. (4) level measured from oil surface to top of upper fork tube. As far as I remember, there are no exceptions to that process I can think of in standard Trials forks. Cheers. Jon

THAT must have been "interesting, Michael! For those of you that are not familiar with the bike, the TM was a 38 HP, on/off throttle, missle and started the used bike ad format: "FOR SALE-Suzuki TM400. Used once-injury forces sale" I rode one a couple of times. The engine would be great for short track oval racing but the chassis/suspension was not able to keep up with the engine. A couple of riders campaigned them in my area with reasonable success, but they were a real handfull to ride. Jon

Fascinating. Someone must be buying them.... The only way these would work for Trials riders is to get two to strap your boots fast to the pegs. Course, then you would fall over and not be able to get up, then you would need one of those gadgets that old people use to call for help when they fall down............ Jon

Cool! I remember going to the Boulder Creek parades many years ago (even before your time, Clive ) but the Trials demo is the best thing I've seen! I bet the crowd loved it. We have the same type of "down home" parades out here is Oklahoma, only a LOT more tractors and hot rods....... Jon

I've also seen a couple of them snap when the capscrew through the bushing is allowed to get loose. That over-stresses the lower part of the lever by spreading the machined tabs on the bottom of the lever that pivot on the bushing. I always advise Loctite on the capscrew and use a little lube on the bushing/tab area now and then. Jon

I'm with Stork. Something or some condition is closing off the system. Usually lack of clearance at the pedal pivot but also a serious obstruction in the bleed hole in the M/C (it takes a LOT of obstruction to block the hole completely) or the rider riding the rear brake (rare, but I've seen riders do it). If the expanded fluid can't back up into the reservoir, the system is "closed" fluid expands with heat and pressure builds up on the pads, which leads to more heat in the system, which leads to more expansion of the fluid and pressure on the pads and things rapidly come to a stop. I'd look for the cause before replacing parts. Jon

I agree. The problem I've faced is that the observers are so busy and focused on the rider in the section they have no time to look out for the rest of the section and everybody knows it, well, maybe not the spectators. To fully enforce the rules, you will need another observer to not be judging the rider but overseeing the section. You can't be focused on scoring a rider at the WTC level and be yelling at a minder at the entrance of the section at the same time. If we are going to fully enforce the rules, we must fully support the scoring staff and not ask them to do the impossible. We might even have more volunteers under those circumstances. Jon

As I remember, the 01' has an Allen pin (I might be wrong) and it is often rounded out by using an old Allen wrench that has worn flutes (aluminum drain plugs are notorious for this) so you might want to get a new set or cut off about 5mm from your wrenches. If it's an Allen pin (5mm, I think?) you might try taking the pads out and using some penetrating oil on it, than use a Torx bit a little larger than the rounded out hole, tap it in and use a wrench to back it out. Be absolutely sure to put some anti-seize on the new pin threads. If it, in fact, is a hex head nut, penetrating oil (take the pads out to not get oil on them) and a slot cut on the head with an abrasive disk in a Dremel tool will allow a slotted screwdriver to back it out. Jon ps. I thought I'd add a little more to the post. The Torx bits are easy to carry in the tool chest and work pretty well on Allen's that are stripped out (dress those Allen wrenches, you'll have a lot less heads stripped out). The Torx bit is tapped in and can be rapped a couple of times to help"shock" the capscrew and loosen the bond somewhat. A short 1/4" socket and wrench can be used to put pressure on the bit when extracting the capscrew. A T-15 works well on 3mm heads, a T-45 on 6mm aluminum drainplugs etc. In a pinch you can also re-install the bolt or plug using the Torx bit untill you get a replacement.