jse

I have a Mikuni VM26 on the 85' TY350 now, never ran a PHBL but I would imagine it would work well. The VM fits right up with no problems and is often used on the older bikes, like the Bultaco Sherpa-T. The "choke" lever and fuel spigot is on the left side, but it's easy to run the line to the tank and by bending the lever down a little bit, it's easy to use. They are fairly easy to obtain and give better response and are easy to tune as parts are easy to come by. I've also got a Mikuni flatslide 26mm that I've modified for a spigot mount and may try that just for fun. I've got a bad case of the "Hmmm, I wonder if that would work" disease and often try things to satisfy my mechanical curosity, which up to this point has been insatiable, but then again, it's also been productive and fun. Jon

As long as there is a passageway, you should be fine. Ball bearings need very little oil (think about ones that only use what oil is in the premix) but they do not react well to contaminates. Bush type bearings (like in some four-strokes) tolerate contaminates to a greater degree as they embed in the bearing shell coating, but they require oil pressure to function. This is why it's important to keep the transmission oil in the Pro clean and fresh by changing it often. Jon

Jan, The slotted end allows you to use a screwdriver to tighten/loosen it if necessary. Cutting the head off allows the tool to be used to install the swingarm shaft as, when sliding it back in, it's sometimes difficult to get the end of the shaft to align perfectly with the hole on the right side of the frame. The bolt helps to align it and also gives good leverage if you need to pull the shaft end around to get it to fit through the frame hole. Jon

I was especially fond of the manual for my 60's CL72 Honda Scrambler. The two full pages describing how sparkplugs are made, including the chemical formula for the ceramic core was fascinating to a gearhead like myself. I remember the very long paragraph describing the construction and ergonomic placement of the handlebars that waxed eloquently on how they had such a positive effect on the happiness of the user and ended with the statement "This could be said to symbolize Honda's kindness"..... I have to admit, I did spend many happy hours on that bike. Jon

The red or green color in the filter oil is a dye to tell you if the whole filter is saturated. You can use a large plastic bag to knead the filter in the oil (don't skimp on oil, you can pour the excess back in the bottle when you use a bag), but the key is to blot out all the excess filter oil with paper towels afterward. Knead the filter in the towels until there are no spotty deposits of oil (and the color is consistant throughout) and you're set. Be sure to squish the filter carefully with your fingers when kneading it and never pull on it or that may weaken the seams. As to the Iridium plugs, I'm looking for one for my friend's Saracen, which takes a 3/8th" thread depth so I think it's a "BPR5SIX" (a 1/2" depth would be a "BPR5HIX". I like the EIX plug as it seems to allow a little "wiggle room" in jetting. I went to the Ute Cup in Colorado last year (same plug still in the bike now) and dropped the main jet size 2 down, but the altitude ranges over several thousand feet in the loop, along with huge changes in temperature and humidity but the bike ran spot on all the time and didn't miss a beat even under the severe conditions that altered jetting requirements. Jon

Stork brings up a lot of valid points and I agree that, if everything else is in good shape, any "correct" plug will perform well. I also think that, with the marginal nature of most bike CDI systems that entended gaps have a very limited return in performance. I've generally found that the early systems, like the MotoPlat, do better with a .5mm plug gap and the newer types work well with .6mm. Although, to do a proper plug check, you'll need to know under what conditions the engine was operating at the time it was shut down, the oil fouled plug will tend to have a glossier finish to the deposits and the over-rich mixture may have a flatter finish and darker color, but as I said, engine operating condition at time of shutdown has an effect and sometimes it's difficult to tell the oil from the fuel fouling. Different fuels will have a different color deposit to the porcelian, some race fuels will have a gunmetal grey and some will have a golden tan to them. Plug condition is an indicator and can give you a direction to go, but other tests, like compression pressure or ring end-gap are helpful too. Sometimes it's not really the plug's fault as poor ground/connections in the CDI or a malfunctioning plug cap/wire can be the culprit. Jon

Mark, I haven't tried the extended gap as yet, wanting to keep the variables down while I'm "testing" the EIX, but it rated as a "wide gap" plug. The marking is "BPR5EIX-11" and the "-11" after the spec.'s is for an installed gap of 1.1mm or .044". Jon, "If it ain't broke, let's mess with it some more!"

It's about 5:30pm here. Sorry, Jan, I misunderstood. Yea, you might want to check the parts number to be sure. As I remember, you have an 04" 300 and I've got the inner seals as #ME250112008 and the outer alternator seal as #MT280212009. What I've done with seals is to get a long socket that just fits inside the seal and use a 10" extention in the socket so that, with the added length and leverage, it's a lot easier to keep the socket square to the bore when tapping it in. Jon

Well, I agree and feel the same way about regular maintenance and replacing parts before they wear out. I used to replace the plug before every meet in my twinshock days, but I wanted to get an idea of an approximate lifespan for the EIX plug by checking for tip erosion, which has been approximately .001" so far (checked with wire, not flat gauges, to be accurate). I ran a new plug for several rides just to compare performance/starting with the "old" one and used a section where you need to lug the engine often and could find no difference, so the old one went back in for further testing. I'll probably change out the old plug soon just for the heck of it, but it has proven remarkably reliable. What got me to try the Iridium plug some time ago was my 02' Chevy S10 Blazer that comes with Iridium plugs that are factory rated as good for 100,000 miles (which I found hard to believe at first), and they have more than proved themselves. So, I guess, to answer the question "are they worth it?", my experience dictates, at least for me, "yes". Jon

Jan, I usually put the bearings in a sealed plastic bag in the freezer for a while, add a little anti-seize on the bearing bore of the case and then lightly tap the bearing in about halfway with a smalll brass hammer and use a press to finish/seat it in the bore. I have a press with special attachments to push the bearing in square but I like to tap the bearing about halfway in with the hammer as it's easy to check that it's going in straight and easy to correct any misalignment as you go. Jon

Yes, it was a great turnout for the first one. The TL250 guy is going to sell the TL and drag out his old Bultaco from the garage. The interest has brought out a lot of old bikes that were languishing in the dark corners (which was my intent in the first place as I hate to see the old iron rusting away- I've got this "thing" about machinery and don't like to see it go to waste). It's amazing how many riders had one or two old bikes hidden away. I'm really looking forward to the next meet! Jon

Well, poop. The chart I tried to post was too small to read well, but I often use Sparkplugs.Com as a quick reference and their subsite at http://sparkplugs.com/sparkplug411.asp has a lot of good reference charts including the NGK codes. "VX" is for high-performance platinum as you'll see in the code chart. Jon

That's been my experience with the NGK BPR5EIX plug. I've had one in my 280 Pro for over a year and now and then I feel guilty and pull it out for a look and gap check, but it's been .024" each time. From what I've found, they have a slightly extended heat range, take less voltage to fire and really resist fouling under severe circumstances (I've never had a misfire or a problem with starting, even after crashing the bike and flopping on me bum, which happens all too often). They also make the 05" 300 Pro a cinch to start easily. They do cost a couple times the standard ES plug, but have proved, for me, to be a bargain in the long run. I'm doing a restoration for a friend on a Sachs powered Saracen and got him a whole new MZB ign system and they specify that an EIX plug is the best to use. Jon

Jan, I got a bolt about 15+cm long with the same thread as the axle, cut off the hex and and cut a slot on the non-threaded end so I could attach a screwdriver if necessary. The device can be screwed in to the axle and lightly tapped to drive it out. It also makes re-installing the axle much easier as you have some leverage to get it to align with the hole on the right side. With the engine back in the frame, be sure to not tighten any engine mounts until you get the axle back in. Jon

I use a stout pick to pull one of the ends outward enough to get another pick in between the clip and the collar, they come out easily after that. Be careful to retain control of the clip as they can spring out rather forcefully. Jon

From what I understand, the curve differential starts at about 2500 RPM. If you want, ask your dealer for part #BT280634007 and the "mode switch" just plugs in to the black/orange wires. Jon

As to: "can my gasgas be ridin with the same abuse?" question, the short answer is "no", but you can go out with your mates and have a good time, I'd just be careful of several things: Jetting, as flat out, sustained speeds will probably lead to detonation and engine damage. Suspension, as your bike will have a lot less fork/shock travel and damping. Geometry, as the TXT is made to handle quick at low speeds. Bike preparation, as to how well you've maintained it's condition. So, go out and have fun, but keep in mind the limitations of your bike and experience. Cheers. Jon ps. Just to keep things equal, find a good Trials section and tell them to follow you for a while.........

I think that's fine. I see that on the GasGas Spain website they usually recommend a "2%" mix, which is, of course, a 50:1 ratio. With the new full-synthetics that burn much cleaner (not a "synthetic blend" type) than the mineral bases, a rider has a lot more leeway to run whatever mix ratio that they are comfortable with. I've rarely seen an engine damaged by more than the recommended ratio of the correct oil. Maybe a little more carbon buildup or ooze, but not actual damage. Jon

Generally speaking, most of us tend to use a full-synthetic premix oil at around the 80:1 ratio (I use 70:1 in my Pro 280 and 50:1 in my air-cooled 85" TY350 Mono) due to the unusual demands we put on the engines (compared to other forms of competition). Richer oil mixtures tend to cause carbon buildup in the front of the headpipe and sometimes oil buildup in the mid and final mufflers due to the on/off/trailing throttle applications (as well as a concern for the possibility of fuel/oil fouling plug problems) and the heat/cool cycles normal in Trials use. Trials carbs (any carbs for that matter) have a hard time providing effective metering in the off-idle area (where the multiple "circuits" overlap--idle/fuel mixture, pilot, slide cutaway, needle profile/height) where we spend most of our time, so our engines tend towards the rich end of the carburation spectrum. The "benefit" (if you could call it that) of this rich mixture and the low/staggered RPM range is that we don't need to demand as much from our premix ratios, hense the unusually low ratios. I'm assuming your bike is a mid-90's JT35 model, for which the factory recommendation was a 80:1 premix ratio. I think you should run whatever ratio you are comfortable with (I'm more comfortable with the "richer" 70:1 ratio myself), I just thought it might be helpful if you had an idea of why other riders opt for the seeming insane lean ratios. I understand how you feel as I come from a background of building high-performance race engines (including TZ, RS, Formula-S etc roadracers) and I thought these guys were nuts to run those ratios, but from my experience in Trials since 1971, engine failure/damage from a lean premix oil ratio cause is extremely rare (I actually can't think of one). They almost always are caused by an "outside" condition such as an airfilter installed incorrectly, low-octane fuel or incorrect jetting. Jon

True, "power" ("horsepower" in some measurements) is a function of torque AND rpm. You can have a measurement of "torque" when trying to unscrew a peanut butter jar lid, as torque may or may not result in motion ("power" has a time/motion element involved and simple "torque" does not). When you look at a HP/Torque/RPM graph, where you see the torque curve peak is where the intake/exhaust system is losing it's ability to fill/evacuate the cylinder effectively. Jon

Geez, I got to admit, that's a wonderful offer, but that's my favorite puller (o.k., maybe my favorite extra-large one) and I've got somewhat attached to it....... Very handy tool, if you have clearance to get it on the bearing, it WILL take it off. That one's a large size but it still can be used to take off small bearings. They also last forever, that one's probably 45 years old and has taken crank dampers off blown fuel Hemi's and steering stem bearings off a GasGas tripleclamp. Jon

I spoke with the race parts supplier about the Evans coolant when I got my race fuel and he said all the hard-core racers absolutely swear by it and it's the best stuff available for high-performance and HD applications. He couldn't supply me at this time as another individual had the franchise, but he was going to see if he could work with the company to carry it in our area and let me know. I could probably order some over the Evans website but I like to support the local suppliers so I'll give him some time to see what he can do. Jon ps. Tell all my old buddies in PITS hello for me!

To illustrate what they are talking about (at least what I think they mean) to those that may not be sure what the tools are, here's a photo of the three-jaw gear puller on the left and a bearing separater on the right. As you mentioned, the bearing separater will not flex. Bolts are attached to it and a screw-type rod presses on the center of the shaft the bearing is on to pull the bearing out. Often you won't need the attachments for the bearing tool as it wedges behind the bearing and pushes the bearing out when the side bolts are tightened. Jon Forgot to mention, the three-jaw gear puller will flex less if all the bolts holding it together are tightened up after it is on the bearing/gear, otherwise the tool can be pretty floppy to work with. Afterwards loosen all the bolts to release the bearing/gear.

Craig, I've got a richer #38 pilot in mine (and have a knurled knob on my fuel screw so I take a second to reset it before each ride for best throttle response) and still have found, like you, that after walking the section, if it does not start first kick, the choke will fire it up every time in one or two kicks. I've heard of this situation enough times before that it seems to be a quirk of some Pros, but easily worked around. On the other's advice about "stabbing" at the kickstart, just make sure you lock up the racheting mechanism first, or you run the risk of eventually damaging the idler gear and/or kickstart shaft teeth. Jon

It's true, Mark, my riding has always been "casual", no matter how hard I try to formalize it.... Actually, I like to sign up Novice-Non Comp and take a group of new riders (and anybody else who wants to go with us) out and help them learn the ropes. We cover everything, from how to sign up, to bike set-up, to rules, to reading sections, to riding techniques and everything in between. Besides, my riding looks fantastic to the new guys who don't know any better............ Jon