bikerpet

This is very much just a personal observation, but I'd be interested to hear how it resonates with others. The last "regular" trial I went to was a bit of an exercise in frustration - I was (knowingly) riding a grade at & above my abilities because I enjoy a challenge and I don't care about placings. I ride for self-satisfaction. That 2-day event saw me really struggle in parts, taking voluntary 5's on a couple of sections. The second day I dropped down a grade which at least let me ride every section. Last weekend I went to my first Gate Trial. Lot's of fun - more fun than I think I've ever had at a comp. Last lap I decided to go for maximum points (11) on every section. I ended the lap with 9 x 0 and 1 x 11, total of 11 out of possible 122. LOL. And had a blast. Totally different experience to getting 5's at the previous event. Reflecting on the difference I realised a big part of it was that at the gate trial I could mostly ride at least the majority of the section even if it was going to end in a failure. There were only 30 or so riders, so no one was too stressed if I continued to finish the section after a dab (failure). There's also sometimes the ability to structure your ride so the hardest obstacle is later in the section. In a regular trial once you 5 then you have to leave the section. If that hard obstacle is one of the first, then you'll never get to ride the rest of the section. So now I'm seriously considering how interested I am in going to more than the odd Trial. I enjoy riding challenging obstacles, I enjoy riding terrain different from my home area, I enjoy riding what others have set. But I'm not interested in spending $100+ dollars and usually 6 hours driving time to go to an event where I only get to ride a percentage of the sections. If the rules where modified so it was OK to complete the section after a failure, even with a very short time limit - say 30 seconds, then it might be different. At least then I'd get to challenge myself, and get to ride everything I can. Of course the other option is to drop down a grade and change my idea of challenge to simply keeping my feet up and getting a much lower score. Strange idea I know. I'm working on changing my mindset to emphasize low scoring on easier obstacles, but damn it, I enjoy having a crack at harder obstacles! I guess it is largely the difference between comps as competition, and comps as practice. I go to comps to ride on something I can't at home, and to ride with others. The competition itself is a very distant third. What do you think? Does it take away from the enjoyment when you have to ride conservatively in order to get to ride everything in the sections?

No pinch bolt. Good plan to mark the nut. It's always loosened off, even before greasing.

Yes, that's why I can't work out why it's so darn hard to keep it tight! I used to just tighten the main nut then the top bolt and finally the fork legs. But it always loosened. So last time I greased it I decided to tighten the bearing right down until the steering got stiff to turn, then tighten the other parts and finally back the main nut off hard against the top tree. Today it was rattling around like ... a loose thing. Beats me how it happens! I've heard others say they have the same trouble. I do note that on the latest model they've changed to a steel nut instead of the aluminium. Maybe that's the solution?

Next little problem. The steering bearing on the '21 RR is a complete Houdini at getting loose. I thought I had it licked by over-tightening the bearing a little, clamping down the top tree bolt hard, clamping the forks then backing off the bearing against the top tree. But no. Loose again. Considerably. It's a mystery to me how it can do that! My next thought is to put a thin rubber washer (I've some 1mm insertion rubber) between the tree and the main nut, then repeat the above process. The hope being the rubber will act to take any movement between nut & tree and also stop the nut rotating. Anyone else got any tricks?

Thanks @lemur , & for the DM info. I'll proceed progressively simple -> complex & see how it goes. Possibly quicker long term to dive right in & check everything, but I'm always optimistic for the quick/easy/cheap fix. In Australia 98 octane is awful in trials bikes. 94 or 91 are much better, along with a 4 plug instead of stock 6.

Background: '21 RR 300 with 180 hours. A few days ago it started missing and spluttering. I figured maybe oiled up from a fair bit of low RPM riding. Took it for a hard Km or two up forest firebreaks and all seemed well. Rode it yesterday for nearly an hour, mostly slow, but a couple Km on a dirt road, but not fast. All good. Today I go to an event and it started missing at RPM while I was warming up. Figured maybe plug, so replaced that. No difference. Hmmm. Checked tank vent and fuel flow out of tap - all good. Carby out and check low speed jet - seemed clean, but gave it a blow out and visual check. Float level seemed a bit high according to the GG dealer on hand so tweaked that a little. Rode OK for 1 lap of 10 sections, right up until I got back to section 1 where it died. Back to the car and carby off again. Connected tank to see if float needle was opening properly, seemed like it might not be. Removed needle, cleaned it and the seat (although it all looked good). Flowing nicely. Reassembled, started & stopped, then lay the bike on the side to check fuel was flowing out the overflow, hence indicating the float needle was opening up OK. Lap 2 OK, until I got back to section 1 where it died once again. At least it lasted until I was close to the car! Wiggled every electrical connection I could find and it started for a while. Dug in deeper and disconnected the kill switch. Started and ran. Reconnected and seemed OK. Got the next two laps in, then as I was mucking about on some rocks it started missing at higher revs, then died again. Wiggled all electrics I could lay my hands on and it started, but I packed it in and came home. It could as easily be something to do with the time spent wiggling things as the actual wiggling. I've heard & read the CDI can display this sort of erratic missing? Possibly the coil failing? But I haven't heard anything about coils failing on these bikes. ? Maybe the kill switch isn't opening properly? Seems an unlikely culprit to me as I wouldn't expect that to cause missing at RPM, rather just erratic death at any rpm. Maybe still carby jetting problem? My plan is to open up every electrical connector and check they're clean. I'll also add dielectric grease while I'm at it (I greased the CDI connector as a precaution a few weeks back - maybe that's contributing?). Also meter then probably dismantle the Leonelli magnet kill switch and check that's all clean and functional. Lanyard kill switch is mandatory for comps. I'll pull the carby and give it a thorough going over. I always run a Mann inline fuel filter so would be a bit surprised to see the jets blocked. Not too sure what else to check, so looking for suggestions. Thanks.

Here's what I've ended up doing. * replaced scrivets with cable ties slipped through a short length of PVC tube. The tube prevents rubbing around the holes. * cut off most of the "hook" on the guard. I cut all the side hooks off and left just 4mm or so in the middle. I also cut between the back and side sections of the rib to give the remaining hook more flexibility - this was probably not a good idea as it now un-hooks too easily. * plastic bolt in the front. I'm pretty happy with this. It has popped off a few times when I've crashed but otherwise nice and secure. If I was to do it again I'd trim the side hooks right back, leave the centre section about 4mm and the whole rib intact. I'd also put a good bevel on the lip of the airbox and the hook so it's easier to snap the two together after popping the cable ties - currently it's a bit awkward snapping it back in place without removing the front screw. I'll do that on this one when I get to it. I'd like to have an easier in-field replaceable solution than the front bolt (I've broken it twice) but haven't figured out what that might be. Still, with both cable ties in the back it stays on well enough to continue riding if needed.

I run stock 10:40 and don't have any problem with it at all. If I want to go slower I slip the clutch, which has many other advantages too. Going to something lower like 9:40 or 10:42 will increase torque at the rear wheel, making it harder to maintain traction when it's tenuous and when you accelerate. Slipping the clutch considerably increases available traction, but does require development of that skill. There is a massive gain in traction to be had by using a higher gear and slipping the clutch rather than using a lower gear. The TRS is definitely pretty snappy on the throttle, but I believe that stuffing around with different heads, reeds, slow throttles, blah, blah, is a poor substitute for learning how to use the clutch. However ... just using a thicker base gasket (or doubling up) is a very quick & cheap way to soften a 2-stroke. Personally I'd far prefer slightly too high gearing than slightly too low. That said, my preferred riding would be significantly more challenging in 3rd gear! I mostly only use 3rd for big hills or when on my way to 4th & 5th. Horses for courses.

Probably like oil discussions, but.... I've used them on a few bikes (still do). My main reason is to provide some scratch protection from crashes - it's not going to stop a gouge from a big off onto a sharp rock, but I know from experience that they do provide a certain level of protection. I believe they significantly reduce the amount of dust that gets into and past the wiper, based on observation riding in exactly the same location over some years with and without. I make my own up out of old wetsuits bought for peanuts at thrift shops using a domestic sewing machine. I make them so they are quite conical so the bottom end is loose around the stanchion but tight on the lower, with the idea that it reduces or nearly prevents rubbing and allows a bit better drying. I've seen some commercial ones that are quite snug on the stanchion - I suspect that could cause abrasion. No velcro in mine as that's a complication that I also expect could cause abrasion on the forks. I remove and clean them when I change fork oil every 50 hours. They are usually very clean inside, just some slight dusty/oily marks on the creases. I don't have any issue with them staying wet, but I ride in Australia, although in an area with moderately damp winters.

The magnet kill switches are generally super reliable & long lasting. You'll quickly get used to thumbing the button off. I like the magnet lanyards, unlike many. I couldn't count the number of times I've dropped or leapt off the bike & the lanyard just kills it. Significantly reduces the risk of blowing a motor from jamming the throttle open in a crash. As someone else said, ditch the elastic and replace it with cord or webbing (eg. off an i.d. lanyard). The elastic will eventually flick the button into your face, which hurts! Or injures. Finally, point the switch base forward toward the clutch lever. Significantly reduces the chance of accidentally knocking the button off. It'll still come off just fine when you want it to.

Yep, same nett result, but getting into the top of the carby is much harder on many bikes than getting into the twist grip!

You'd probably have been able to make and fit a stop like I made in less time than you've spent posting here! Just try it. Seriously, it took me under 15 minutes to dismantle the throttle, measure, cut some plastic, heat it, trim & re-assemble. Cost absolutely nothing. You could use some sturdy cardboard to try it for 10 minutes or so. It's dead simple, no precision required at all.

Judging oil ratio based on smoke seems a very arbitrary criteria. The base oil can make a big difference to the amount of smoke and obviously 'smokeless' oils are going to have totally different visible smoke threshold to regular oils. Of course the acid test is whether the engine sustains damage - if not all's well. I did once read an article where they measured power output with differing oil ratios. They went to great lengths to isolate the oil quantity as the measured variable - accurately calibrated jets to maintain consistent fuel/air ratio, etc. I forget what ratio gave max power, but it was at what I would consider an insanely high amount of oil. So lubrication is a significant factor to how freely the engine spins. Yes, I know, who'd have thought? I don't really consider this "engine damage" - a decent clean and it came up good as new, or at least good as a 130 hour engine. Excessive maintenance - yes, damage - no. I really suspect now that the problem probably spiraled from a build-up causing the rings to get sticky which allowed more build up on the bore, more blow-by, so more sticky rings etc. What caused the initial stickiness is anyone's guess - could be too much oil before I got it, or the Putoline I was using, or not enough time by either the previous owner or me at high power (previous owner only rode shows on it). I'm not overly convinced that going from 100:1 to 93:1 is a significant factor, but certainly not ruling it out as contributory. Take your pick. I'll be adjusting all 3 variables in future.

It depends which manuals you read, or not. Sherco & Beta above. All my quotes for the various manufacturers were directly from manuals on the manufacturer website, perhaps different year model to the ones you looked at. They were examples, not intended as inviolate gospel. Manufacturers change oil suppliers, I'd guess due to changing financial incentives as much as anything. They also choose a supplier for their entire range, not discipline specific, so it's always quite possible they have to recommend a less than ideal product because that's the best in the suppliers range. But I doubt any of them are going to recommend an oil that they believe is likely to cause serial consumer problems - that's financially not viable. I would have to question if the UK Sherco importer has or had a relationship with Rock or Ipone - I wouldn't have a problem if they did, but it would cause me to wonder if the oil was chosen purely on it being "the best". I don't doubt that Motul 800 isn't the best oil for trials, I seem to recall looking at it several years ago and noting that it had quite high flash point which tends to suggest it needs a higher temp to burn clean (it's not a direct reflection, but a loose indication). My point was that it's sold as fully synthetic, like all the others. Putoline made it quite clear why they have a trials-labelled oil but also suggest using a different oil, and it mirrors what I just said - financial imperatives often influence what's available and recommended. I certainly accept that, hence why I'm not wedded to a particular brand of oil or believe it's strictly essential to stick exactly to manufacturer recommendations under all circumstances. I do take away from this that my assessment of what is a good hard ride is obviously not appropriate. I'll re-calibrate my mind. Rhetorical question - I wonder how the manufacturers determine 100:1 is the magic ratio of fuel:oil for all trials riders under all conditions, rather than, say, 90:1, 95:1 or 105:1? My take-away remains that I'll move to a full-synthetic oil at 100:1. Which one will be determined largely by price, availability and more frequent monitoring of the bore and piston.

You're over thinking it. It's not about combustion temps being "wrong", just the simple fact that if you light more and bigger fires it gets hotter. ie if you rev the bike hard under high load the combustion chamber is going to get hot. Pretty simple. As Putoline said in their reply, if you run an engine hard you might need more oil. The manual figure is a guideline that should be sufficient for typical intended use, no more, no less. Adding oil also makes the effective mixture leaner (more oil, therefore less fuel per unit volume), so if A/F ratio is the be-all and end-all then adding oil should increase combustion temps and so improve oil burn. Generally not so. I've been running around 7% extra oil - I doubt that's the single biggest contributing factor here, just one of several. I used to manufacture nano-light aircraft (sub 70kg). Those engines get hammered on climbs, wide open for prolonged periods against a prop that was designed to keep the engine almost exactly at peak power, but dawdle around once up and using thermals or ridge lift. My most popular engine used to sit at 10,300 rpm for as long as you wanted to climb - sometimes 15 minutes+. 50:1 edit: I racked the memory banks and remembered it was 32:1 full synthetic was very marginal to keep them safe on climbs, but you had to give them regular revs once up and just dawdling along or they would oil up in fairly short order. Yes, there's a reduction in O2 at altitude, but I can assure you the same effect could be seen even if you were ridge soaring at 100ft amsl.

I thought my hills would be enough - the exhaust is often smoking after a good climb, but I do tend to take it pretty easy most of the time and tend to back off if I see the exhaust start to smoke - I'm nervous of melting exhaust guards having done that on a couple of bikes now. I was quite impressed that Putoline took the time to respond too. They definitely get a gold star from me for being responsive and not dismissive. I'm reasonably happy that a change of oil and a bit more right wrist action should solve this problem in future - once I've gone back in and cleaned the piston & rings up fully.

Yeah, I get that. I opted to go just slightly over 100:1 (93:1) because I regularly climb fairly steep hills several KM long climbing several hundred vertical feet (up to 1,000 vert feet). I figured it was safer to run slightly more oil than the 100:1 to allow for that non-typical trials use. Obviously I'm too gentle on the climbs (I often muck about doing trialsy things on the way up) to clean up the oil.

GG recommend GRO Performance 2t. Fully synthetic. Beta & Sherco recommend Motul 800. Fully synthetic. TRS show Nils Duo Synt S. Fully synthetic. Putoline technical support manager advises fully synthetic. I'm going to take the hint.

Being someone who believes in going to the source wherever possible, I emailed Putoline about this and today heard back from them. I asked if he had a preference for MX7 or MX9 in this case: The TT Trial Pro is labelled "synthetic", but I guess that really interprets as "semi-synthetic" rather than "fully synthetic". I'd assumed it was synthetic as in "fully". So I guess I'll try the MX9. I get a good price on Penrite (Australian brand) from my local distributor who I try to support wherever I can, he also sells Putoline so it might come down to Putoline vs Penrite price. I'm sure there's differences in the full synthetic 2T oil offerings, but I'm also pretty sure that I couldn't pick the difference based on the marketing guff. Anyone want some discount TT Trial Pro? 😄

Looks like it, but not. 100% confident that hasn't happened. That sounds logical to me. Under that scenario the Putoline may not be a cause. It could be that given the quantity of oil in the exhaust when I got it, the rings stuck quite early due to excessive oil, then the Putoline goo was a consequence not a cause. Or the Putoline could be crappy. Or I just might need to go for a solid blast from time to time to keep things clean. That seems a bit odd - my riding spots are several km apart on hilly forestry road so it gets a reasonable run most days. But I just tootle along usually, maybe more speed required.

Thanks Paul. I was going to give you a call. Fan's working fine. The skirt looked OK. Quite a bit of brown muck between the rings though. I'll order the gasket kit from you & then pull the cylinder off so I can clean piston & rings properly.

I can't answer your question, but I used to remove the airbox cover screw and tape the cover semi-permanently to the guard, then use cable ties or nylon bolts at the rear fasteners so the guard could pop off without breaking. Effectively I converted my 2017 & 2020 Evo guards into ones similar to your 2010. I found it no problem to just lift the guard and change the filter and far preferred not breaking an expense guard in crashes. Going to a new style guard might not necessarily be an upgrade as much as a downgrade in my view.

I reckon they all put something so they smell other than burning oil - they've all got distinctive smells, just that Putoline try to market theirs. In Australia so our fuel is different to yours, but 95 octane bowser petrol. What nearly everyone here uses. Some people use 98 octane, but weirdly that often doesn't run as well as the standard 95. Exhaust packing seems pretty good - I had it out just a few weeks ago when I belted the exhaust cap off.

I went to start my '21 TRS RR 300 (120 hours engine time) today and found it was jammed. Weird, as it was running fine yesterday right up until I stopped it and put it away. I'd just checked the coolant the day before and it was still correct level so I was comfortable it hadn't cooked from lack of water. I also knew 100% that I had oil in the fuel - 140ml to 13L as I've used all along. I had heard a slight and intermittent rattle for about the first minute while it warmed up, but couldn't identify where it came from. I tried the screwdriver to the ear trick over parts of the engine and it didn't sound like it was coming from anything I listened to. I pulled off the clutch side and could find nothing wrong there. The clutch basket rotated freely on the tiny bit of play in the primary gears, so it wasn't the clutch or starter gears, and the gearbox moved fine when I pulled the clutch so it wasn't that. Took off the magneto cover and there was absolutely zero movement on the flywheel. So I figured it was crank or piston. Pulled off the head and there was a lot of glaze/varnish - not sure the correct term for burnt on oil? Hmmm. I decided to put a socket on the crankshaft and see if some judicious force would move it. It broke free reasonably easily so I moved it to bottom of stroke. Looking at the circumferential lines I'm thinking maybe the varnish hardened up when the bike cooled and stuck the rings to the barrel? I got in there with a plastic scraper and cleaned a fair bit up, then more with a Scotchbrite and some contact cleaner. It came up virtually good as new, not a scratch in sight and nice OEM hone marks. Hooray. Also cleaned the carbon out of the head and piston top. Nice and shiny again. Put it all back together and it started and ran as well as ever. Phew. It had the same rattle for a couple of seconds after it started, but then gone. I'm tending to think it sounds more like something external than internal, but that wouldn't go away as the engine warmed up. Odd. I'll do more investigation when I hear it next, if I do. I'm a little nervous about that. I'll probably pull the barrel off and give the piston and rings a clean once I've ordered a gasket & O-rings - I've got a trial tomorrow so wanted it back together. So I'm wondering a couple of things: I've been using Putoline Trial, which I've previously done hundreds of hours on in Beta's with no issues. But now I'm wondering if Putoline is known for gumming up the works? Is this a "thing"? That rings stick to the build up in the cylinder when it cools. Or should I be looking deeper for a more significant cause? I wish I'd taken a photo before reassembling, it looked vastly better than this! Thanks for any enlightening comments.

I believe you can fit 10 / 61 gearing. Should help everything except top speed, & who cares about that, just enjoy the scenery a bit more.