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Another thing to check is the routing of the overflow hose off the radiator cap. Things are quite "busy" in that area where most of the electrics reside and some riders will run the tube over the crossbrace, where the bottom of the fuel tank will pinch it off. When the coolant heats up, this will allow enough pressure to build up in the cooling system to force coolant past the W/P seal into the tranny fluid. If you replace the waterpump seal, check the shaft for wear and if there's a significant groove on the shaft there the seal lips ride, replace the shaft also, which will prevent a premature failure of the seal in the future. Jon

My only problem is I don't know what to wear underneath the kilt...... My relatives on my mother's side are from Scotland and the Isle of Man, you'd think I'd know the answer. According to my Great Uncle, the answer would mean I'd have to worry about pipe burns on some VERY sensitive parts..... Jon

We can usually get bearings like the 6004RS in most bearing shops here in the U.S., but they often cost more than GasGas dealer retail list. What I can't figure out is fork seals, which are unavailable from what I can find out, in any regular bearing/seal shop, even though they are standard Metric double-lip types. Jon

I bought a bunch at the Sooner Cup too (Clive will be happy to know I sent one to Jim). I'm going to have a couple of them made into a kilt, I've heard it will shave off 10 points per section....... Jon

I'm not very familiar with the MH200, but I may be able to give you a couple of general things to check first. There are usually two springs that can be checked by taking off the clutch sidecover and pulling off the clutch basket. The centering spring is what returns the shaft to the centered, neutral position but since you say the shaft centers on the shift to 2nd, that's probably not the problem as when that breaks it usually won't center up or down. The other spring is on the "claw" (on the end of the shiftshaft arm) that holds it against the pins on the shift drum "star". It may be bent of possibly broken. Another thing that might cause the symptoms you describe is a bent shift shaft. Sometimes, when hit by a large obstacle (i know, something "unusual" in Trials), the shaft will get bent and since it goes through the cases (and the "bushings", or bearing surfaces, where it contacts the case are fairly far apart) will tend to bind, sometimes in the way you describe. I'd take the shiftshaft out and check it for straightness. It can usually be straightened with a set of small V-blocks and a press. Jon

I was always taught by my Engineer buddies to remove the modular components (CDI etc.) before welding and always ground the welder as close to the welding site as possible. They seem to think the welding vs. fried electricals experience came from a welder grounding far away from the weld site and the current flowing through the frame (and components also) but they take off the "expensive stuff" before welding. I'd also check all engine mount fasteners (clean and re-torque) as the engine is an included part of the frame, which is usually a diamond shape with the engine in the center as a brace. Generally, even a slight amount of movement at the brace (engine) will flex, and therefore stress, the pointed ends of the diamond, i.e. the footpeg area and the headstock (steering stem) and cracks will form. You'll want to loosen all engine mounts, weld the frame and then tighten the engine mounts after cooling, which should relieve any stress areas. Jon

Mark, you have solved my problem! Based on extrapolation from previous experience and gleaning small nuggets of deep wisdom from your Budda-like advice, I now take all my readings with a Cresent wrench (covered with a condom, of course, to keep my probe clean) and, voila!, all my readings are now consistant! Kidding aside, it may be that I've been expecting "grading on a curve" information from a "pass-fail" testing instrument. I know that, in the race shop, we often had to resort to the "replace highest-suspect, single item at a time, with a known good component and re-test" technique when all else failed. Jon

I worked part time with some friends in a race shop tuning MX, drag and RR bikes and just about every time I'd run a meter on the various electrics (injection and CDI, for instance) and compare the measurements to the published spec.'s, I'd somehow be off a lot of the time. Drove me nuts! (o.k., now you know why I act the way I do.....). I used a good Fluke meter and was very careful, but it seemed like I often got a reading out of specified range, even though the bike ran great. Either the factories are using special calibrated meters or I am, indeed, electrically challenged....my guess is the later. Maybe it's the fact that I can't actually see (electrical properties) what I'm looking for, but Lord knows, I've felt it a time or two, especially the jolt I got one time from a Scintilla Vertex mag on a supercharged Keith Black engined dragster, the sucker instantly tightened every muscle in my body and knocked me about 12 feet back (well, there's another reason I act this way....). Since this is "mechanical talk", I guess my question is on topic, but is there any "trick" to taking readings that provide consistancy? I know there are a lot of sharp people out there and I could sure use some pointers. Jon

copemech "He He, yea Jon, I noticed! Glad I did'nt get a lecture ! Ha! But seriously, with reguard to the bikes that spec the standard NGK BP5ES as an example(not speced for a resistor) the addition of a resistor in an already weak(specially at startup) ignition cannot fare well in my mind. That resistor is just another obsticle in the chain. For those that have never broken a sparkie open, it is just a carbon pile put in series to reduce secondary ignition spikes production of RF signal generation throughout the leads. The modern auto ignitions can easily overcome this added resistance and even run gaps as high as 40-50 thou even with the smal COP(coil on plug) systems, because they have some good stable input voltages that the simple flywheels cannot provide. When put into the science of a trials bike(if there is any), you need to get all you can get out of what little is available as far as electrical power and coils go! Plugs too! I still see many recommend a .020 standard gap for conventional spark plugs to run reliably. The standard plug electrodes can actually shield spark exposure at that minute gap This is where even a resistor type platnum or irridium has an advantage, even at a closed gap, because of the more open exposure of the electrode design to actually doing the job of igniting fuel mix! The one benefit may just overcome the downfall in a given situation." This is an area where my expertise is a little short. I had the same question many years ago when living in Silicon Valley so I collared some of my MSEE buddies and posed the "resistor vs. non-resistor plug" question to them. They seemed to agree that the RF interference area aside, they couldn't really say that a resistor plug was necessary unless they had all the spec.'s on the CDI to draw a good conclusion. They could think of some instances where a resistor plug would compliment the ignition system and would be necessary. Some later model automotive engines must use (non-inductive) resistor plugs for a proper "talkback" to the electronic ignition. Outboard marine Capacitive Discharge Ignition (CDI) such as those used on some Johnson and Evinrude marine engines require a special inductive type resistor (such as a Champion Q-type or NGK Z-type) and use of non-inductive resistor type plugs on these motors can cause misfire and poor performance, but I'm not positive if the same type of relevant question holds true (in the resistor vs. non area) for Trials bike CDI's. As for gap, I usually recommend .020" for the earlier and less "robust" CDI systems like the MotoPlat and .024" for the newer systems (two-stroke), but if your bike seems to work fine at a larger gap, I don't see any problem. The auto plugs can be run at much larger gaps due to their ignition and engine management systems, and the number after the dash on the plug indicates the recommended gap, usually the numbers range from "-8" to "-20", which is a gap from .032" to .080". I would think that with an extended gap that is too wide in a Trials bike engine, there would be the distinct possibility of misfire under certain conditions. Trials bikes are a very weird animal and are tuned to perform under an unusually strict set of conditions and due to compression and CDI/jetting mapping, for instance, can self-distruct when those conditions/limits are exceeded. A long high-speed run on a highway (generally no problem with most other well tuned engines) can easily turn a Trials engine into a very expensive boat anchor quite quickly. Hmmmmm. I guess what I'm saying is that I don't have an exact answer to the question posed, based on available data. Jon ps. Don't worry, Mark, I'm saving up several lectures to give you all at once.......

Let me tell you, I've stripped out more than my share of fasteners. My problem is I develop a "personal relationship" with certain tools and they are the first ones I reach for and I really hate to replace them. I know I've got a 3/8th drive, 1/2", 6-point long socket I always use that has to be 45 years old at least. Darned if I know why, it must be the fit or balance or something else I can't figure out that causes certain tools to be my favorite. Jon

As usual, the riders and helpers were a delight to be around and they are what makes it work. I thought the staff planning was excellent and their creativity paid off in a very well run event. I love to check and was able to do so on Sunday after getting a bunch of photos of the Saturday morning Amateur riders and the Pros were very impressive. What really impressed me was the tenacity and drive of the younger Pro riders, some riding that class for the first time. We've got a good crop of riders coming up. Pat Smage is a wonder to behold and the harder the section, the more his talent shines (and, he is a really nice kid). After we goaded him to do "something spectacular" on his last ride through section 8 on Sunday, he treated us to a high-flying "heel clicker" out the end of the section after his way up a huge 20 foot boulder wall, causing many lower jaws to hit the ground..... Jon

Just remember that when I saw you yesterday at the Sooner Cup, I didn't mention this........ Jon

Neat! It's a heck of a lot easier to ask for a "4" rather than a "NDVK16PRZ11"! I'll pass that info off to my Beta buddies, thanks Dan. Jon

Matt, I'm not aware of any left-hand threads on any sump plugs (I can't quite figure out what the advantage would be). If it's an aluminum Allen plug like the larger GasGas Trials models (or any other bike) be sure to use an Allen wrench in good shape so the plug is not stripped out. It's common practice for T-handles, for example, when used often, to wear the sharp edges at the end and they will be prone to rounding out the plug (the mechanic will usually blame the part, but it's usually the fault of faulty tool maintenance and improper torque). Every once in a while grind off about 7-8mm from the end and lightly dress it, which will expose a new surface that will grip the inside of the plug, as designed, and you'll never have a problem with stripped plugs or capscrews. Most plugs are torqued to 9-10 ft lbs or 12-14 Nm, which is probably much less than riders think it needs. Jon

I'm assuming you adjusted the eccentric bushing correctly rather than just moving it around as that adjustment is very precise and there is a specific way you go about it. The proceedure is covered in the U.S. owner's manual DVD that comes with every bike sold in the U.S., but you can access it on this website: http://d-mis-web.ana.bris.ac.uk/personal/H...f/media/gasgas/ , under #12 "engine_adjustment" (I love that website). The other piece you mention is the washer/bushing that the centering spring slides on (it kinda looks like an old stovepipe hat, same as the clutch servo cylinder) and theres a small steel piece that is brazed on the end and fits into the slot at the end of the shift shaft. This will sometimes snap at the braze point if the shifter is hit hard by a rock, but not always. If that was the problem, the shift lever would usually flop around without centering itself, so my guess is that it's not the problem. I may have missed something else to check (wouldn't be the first time!), but if the shift centering spring is set correctly and the spring bushing/centering spring is in good shape, you may need to go inside the engine and look for bent shifting forks or a bent/broken limiting roller or roller springtab inside the shift drum. Good luck. Jon

I've tried just about every plug I could get my hands on in my TY350 and Pro (my poor old test mules), some with numbers and letters on them that would take up half a sentence (o.k., maybe I hyperbolize a "little", but how bout a "NGKPZFR7G-G" or a "NDVK16PRZ11" for example)....... I've settled on an NGK BPR5EIX at .024" gap. Fairly easy to come by, although you usually have to have the bike shop order them as they don't usually stock that hot a plug. Compared to the standard plugs, they take a little less voltage to fire, resist fouling and have a slightly extended heat range. The ignition curve ("map") in the CDI system on the modern two-stroke bikes kinda looks like a bell-shaped curve sloped to the right. The ignition-point-at-crank-degree will advance to a certain point and then retard at higher RPM's. Some two-stage systems will essentially "move" the curve left or right (starting earlier or later BTDC, but following the same path after), with the shape of the curve the same. Other two-stage/multi-stage systems will change the shape of the curve. I think the GasGas has had both on their Trials models at various times. Jon

Should be 300cc's per fully drained leg. 5-weight is what the facory recommends. Jon

Probably better to get a set from your dealer, I'm not sure what size they are. I think there are two types, one with separate seals on the outside and a longer bearing with the seals as part of the bearing. Don't forget to lube that set inside the lower front part of the swingarm, a lot of riders forget that one. It has mushroom shaped bushings so don't try to drive them both out from one side, use a sharp drift to catch the groove where they meet inside the swingarm and drive one side out at a time. Jon

Dear Sensitive Tush, How very sweet of you to think of me when looking at an oily fork spring...... I agree, I don't think any rider needs to do all the stuff the way I do. Just following regular maintenance guidelines would keep the newer bikes in great shape. You changing fork oil once a year is probably more than a lot of riders do, and I bet a lot of bikes are sold to the second owner with the factory oil still in the forks. Steve had his 250 out last Sunday when we were setting up sections. That's a really nice bike. It's hard to sell the U.S. rider on the choice of a 250 (over a 280 or 300 offered) as we tend to have the cowboy attitude that bigger is better and we want to supersize everything. When you ride it, you can really understand why the Euros like it so much. Very responsive and smooth and I would think a better choice for a lot of riders whose ego overshadows their talent and who buy a 300 and then want to tame it down. The 300 is great for a lower class rider who rides Colorado and Donner now and then, you can't beat them for high altitude work. Jon

Mark, It's real easy to get nutty about what fluid to run in wet-clutch bikes, especially Trials bikes, whose clutches get a real workout. The same goes for suspension where, for instance, I will choose a different type of shock fluid depending on (irrespective of other factors, like viscosity, and that would depend on how that viscosity was measured-and at what temperature, the riding style of the rider and the general type of track the bike was used on etc.) if the shock body was steel, raw aluminum, anodized aluminum, treated or non-treated magnesium, coated (and it depended on the type of coating) etc. See, Mark, with all this kind of stuff in my head, you now know why I act so goofy.... Here in the U.S. a good place to start is the brand importer as they are kinda like a "hub of information" (or should be) that will get feedback from dealers and riders. I like to recommend fluids that are easily available to the average rider and that I have had personal experience with and not the space-age stuff made with unobtainium that couldn't pass a radiation detector my aerospace engineer buddies are always trying to con me into trying. I've generally found that a light tranny oil, changed frequently, has given me the best performance. For the GasGas earlier models, like the "Edition" engine, I ran DexronIII ATF in my JTR370 (which is about 7.5 weight), for my 02' 280 Pro (with the Magnesium engine) up to the 05', I think (when they changed to a thinner Bellville spring) I run the GM AutoTrak II transfer case fluid, and the 06' on up seems to work well with Ford Type-F ATF, which has a little higher heat tolerance and a little more "bite". If I had the DOT-3 clutch, I'd switch to DOT-5 (Silicone, which seems to have a little better lubricity than the brake fluid) but that entails flushing out the whole system, not just bleeding off the line and dumping new fluid in the M/C reservoir. I like to change the fluid every 5-10 hours of use or after a nasty, wet Trial. Theres other things I do, like run a magnetic plug (like the lower one for the case drain) in the upper sidecase oil filler to catch all the fine metallic particles any engine normally makes, use a modified Suzuki lever that has a flat blade that's more comfortable for me, polish the servo and master cylinder bores with ultra-fine Cratex abrasive, blah, blah, blah. Since I can't ride for squat, I take out my frustrations on my poor bike by messing with it all the time........ Jon

\It was 68 degrees and sunny when I left Tish a couple of hours ago. A little cool in the morning but just a sweatshirt was almost too much in the later sun. Some nice water in the creek and lots of nice grippy quartz composite rocks to hop on and great moisture content in the ground without being sloppy. The Amateur (morning and afternoon levels) sections look good and the Masters shouldn't complain they are not challenged enough with technical stuff (many of the Masters ride Nationals and like an above average difficulty Trial for practice) and the lower classes will have fun. I rode the loop several times cleaning sections and even I didn't get lost... The Pro sections are spectacular to say the least. Very spectator friendly and most easy to get to by foot quickly with #1 just below the house. Brian was talking about having the Pros ride a couple of sections at a time before moving on so the spectators can follow the action. Shan will be up North at a Supercross so I'll try to get some shots for TC. The Pro sections are very photogenic! I'll be down there early Friday to run the Pros through tech. See ya'll at the Cup! Jon ps. I told Ma Nature to hold off on the snow till after the Trial, even though it would make a lot of Northern riders feel at home.....

"So, started with brake system completely empty. Took top off resevoir. Connected my syringe to bleed nipple. Tried pushing fluid in . . . . . and nothing. Couldn't even budge the syringe Tried it with the brake pedal depressed and not depressed, no difference. Does anybody know the cause for this? Reverse bleeding seems to be the best way, but everytime I tried it with my clutch like this it failed aswell. Just couldnt push the syringe. Is it something to do with the adjustment of the master cylinder "plunger" (technical term) Does it have to be adjusted right out/in?" My experience is that when you can't get fluid to pass through the system with the bleed fitting open, it's usually caused by the master cylinder piston not returning fully back to it's stop at the circlip (rear/front brakes and clutch system). If the piston does not pull back, the bleed hole between the piston bore and the reservoir is not open and the system can't equalize. Generally it's caused by not enough slack where the lever adjustment screw meets the plunger or a sacked piston return spring in the master cylinder (there's an old mechanic's joke about "piston return springs", but they, in fact, do exist). As for air in the system, the first thing to do is to think like an air bubble. I know it sounds kinda dumb, but keep that in mind when carefully looking at the whole system from master cylinder to bleed screw on the caliper. Every system has high spots in it where an air bubble will hide, often at a fitting that can be "cracked" (opened very slightly and tightened again while the system is under pressure). As the master cylinder stroke displaces only a small volume, you might take the brake lever off and use a #2 Phillips screwdriver to push on the piston to get a full stroke. Sometimes the angle of the master cylinder or caliper traps an air bubble in a fitting or loop in the line and you'll want to take the part off to rotate it in a way to allow that bubble to pass through the line to a point where it can be bled out. General practice is to use an agricultural syringe and pressure bleed the system from the bottom-up, rather than top-down. This way you're not fighting the natural course an air bubble travels, which is always up. This will also sound "dumb", but a lot of riders, as a last resort and after pulling out most of their hair out trying to get an air bubble out of the rear brake system (bleeding the rear brake system can be problematic and it only takes a very small bubble to mess things up) will remove the fuel tank and using a tiedown strap, will hang the bike up to a strong rafter by the back tire so the bike hangs straight down. After a day, the air in the system will rise up to the highest point, which is usually the caliper, where it can be released through the bleed screw. Jon

That's neat! Thanks, I've archived that in my data files. Jon

John, I think they gave you the bearing for the later model tripleclamp with the aluminum stem (#BT280210008, "32004X" bearing, ID 19.95mm, OD 41.98mm) but you have the steel 17mm stem (the tripleclamp looks exactly the same) and I think the GasGas number on that is probably #C140100 but I don't know the standard bearing number for it. Jon