cornishflyer

Thanks. I keen on saving some money, a lot more since I've opened the cases and discovered what else needs to be done. Obviously not as keen as the skinflint that serviced the engine before me though. I can't "feel" and up and down play in the big bearing when I pull on the conrod but I can see corrosion in the small bearing area so should just replace the whole thing to be safe.

Thanks bullylover, that might explain the slop. I thought the crank might have spread but when the pin is protrudes out of both sides. I can't see any markings on the conrod itself to say it's the correct part, but the pictures I can see on the net do look similar. Out of interest, why replace the whole conrod and not just the bearings? Surely the bearing would wear faster than the conrod?

Took the crank out and used LOTS of heat on the seal sleeve and still can't get the thing off. I need to send this one for a crank rebuild anyway so hopefully they can get it off for me. Who knows what has happened here, but I don't think much of the previous owners rebuild work, the cases were sealed with bathroom silicon.

Thanks feetupfun, once I split the cases I'll know, but I also fear that the crank webs have been pushed apart somehow. Either way I'm going to be needing new bearings, seals and con-rod kit at the very least. Once I get this seal sleeve off I'll report back.... cheers.

Hi all, I'm just starting to tear into the engine I got with my #158 Sherpa basket case project. There has obviously been a pretty catastrophic failure at one point, the magneto side is full of corrosion, I guess it was full of water for a long time. The cases where completely void of any oil. The crank didn't turn. When I removed the clutch side cover I found that the nut holding the flywheel on was completely undone and floating around, there was no lock wire on that nut, nor the clutch nuts. The area around the woodruff key on the crank is a bit mangled, but I should be able to clean that up. 1) I have two questions. The primary side seal interfaces with what looks like a flanged collar that slides onto the crank. How does that come off? Is a small flywheel puller enough or do I need to use some heat? 2) What is the side play supposed to be on the con rod in the crank webs? Mine seems to be around 5mm which seems crazy big. Cheers

Hi all, I've just taken delivery of a Sherpa T 250 (serial 158) which is about 80%. I want to treat as a slow project to perhaps do the odd twin shock comp, don't want to go mad polishing and that, want to ride it properly. First thing I need to look at is the bottom of the frame, and the clearance to the engine. the frame is in pretty good condition but the bottom rails are a bit squashed, I would imagine there should be more clearance to the engine that this shouldn't there? It feels like the engine is sitting on the rails at the moment. Cheers

Without wanting to complicate things or upset anyone, here is a picture of a cylinder head and piston after running Maxil 427 (not even a whole bottle since the last rebuild). This is not from a trials bike, it's actually from my tuned vespa that does get quite hot and gets up to high revs quite a bit (which is why I was using castor oil). The rings stuck in the grooves which robbed the bike of compression, and the cooked on oil was really hard to get off the head. I was running at 2%. I'll be running Motul 710 next, which seems like it has as good flash point match for my sort of bike. Anyway, that's from my experience - perhaps things are different when running in a trials engine.

I reckon..... 2014 doesn't sound very old, but the first thing I would look at is the condition of the basket. I had to "service" my 2007 250 clutch recently which made all the difference, it's as good as new now. By service I mean remove the basket and look for rough edges on one side of all of the tongs, and smooth with a file. I also roughed up the steels and cleaned the plates, checked none were bent and soaked in oil before reassembly. HTH

Thanks all, yes it's a 2 stroke. Good explaination oldjohn, I'll check the obvious things over the weekend. Cheers,

Bit of a newbie question.. My bike is four stroking when I'm attacking big climbs. I'm going to start looking at needle clip position/air filter first and reckon it's a simple enough fix but I did start to wonder about what happens when riders rev their engines to clear them before big climbs. Mine tends to clear when I hold it wide open for a few seconds as well. Is that clearing the carbon from the plug or something else?

Thanks dadof2, maybe I should look at some old rugby jerseys

Thanks Jonnyc21, I like the look of their stuff, just finding out if they ship to Sydney. Cheers,

Thanks dadof2, does this mean that trials tops are made of a different material or is that only some of them? I live in Sydney so the ventilation isn't really an issue.

I'm not really into the look of the trials jerseys on offer, the MX selection is much wider. MX jerseys seem to be cheaper as well. Without wanting to come over all fashion conscious (which I certainly am not), is there a difference between MX and Trials Jerseys? Is it just the fit? Cheers,

Thanks Tim, that's exactly what I was looking for.

Hi oni nou, That photo was just to illustrate the angle, hence no lock screw. There is actually around 3mm of travel at the lever, but there isn't any free play at the adjuster side because of the spring underneath the rubber boot. Perhaps the problem is that the push pin is not seated correctly.. I'll need to check that. The original AJP lever positioned the adjuster square onto the plunger. To me it looks like the lever I ordered, which was supposed to be a direct replacement, has the adjuster too far from the pivot point of the lever.

Does anyone know which levers work with 2007 AJP clutch master cylinders? I've just received a replacement that was supposed to work but the angle at which the adjuster acts on the plunger is so acute it's seriously affecting the smoothness. The distance of the threaded adjuster hole is greater on the replacement lever than the genuine AJP lever (the left silver one in the picture). I'm told the AJP levers are no longer available, so what would be a good replacement? Thanks in advance.

Shudder, that video scared the hell out of me. Definitely not your typical home DIY job.

Thanks everyone, Good to know it's ridable with this little rebound damping. I'll put it back together and just ride it I think, until I get better at riding I probably won't notice that much, I'm not attacking sections fast yet, just pottering around. My mate is able to do rear wheel hops and all sorts on it so I guess it's still more than enough for me at the moment. I'll need to address the linkage slop at the same time, perhaps a project for a rainy day. Cheers,

Thanks for that informative reply oni nou. I'm pretty surprised this shock doesn't have at least rebound adjustment, even my mountain bikes have had that for years. I'll remove the shock and try the push pull trick. I wasn't able to find the link you mentioned (EDIT: Found it changing the site to Spanish). Mine is like this: I haven't worked out how to undo the bottom bolt yet, it seems to be obstructed with the lower suspension linkage, but I haven't looked properly yet. Thanks for the reminder about the carb by the way.

Hi all, Does this look like an original shock for a 2007 250? I can't find any damping control on the shock, or in the manual for that matter. It's pretty bouncy, certainly compared to a mates 2015 290, so I'm fearful the shock is due for a rebuild, if that is even possible. Cheers

Hi Copemech, There's a couple of places over here that do it from what I can tell, one around $270, the more expensive at $500 but apparently most people use them. Another option would be to send it over to the US but that seems pretty drastic and would take a fair time when I really want to be riding. That said it's too hot to be riding at the moment anyway, been over 40 degrees in Sydney the last couple of days.

Thanks oni nou, I saw that one but I have already purchased a new B piston. Just waiting to be able to afford the re-plate on the cylinder. Cheers,

Just to update, I cleaned up the piston and very lightly cleaned the score mark in the cylinder with emery and put it back together with new little end. As predicted the slap is still slapping. I did order a B size piston though and tested it in the bore, the wear is pretty inconsistent down the bore, pretty much perfect near the bottom but out by almost 0.1mm near the middle. I'm now looking for affordable (to me) nikasil platers here in Australia and then I'll do the full replacement. I did notice that when I refilled the radiator I used quite a bit more coolant than came out of it, a bit of a concern because it was only just recently topped up, but that's for another thread. Cheers.

Surely the obvious is self balancing bikes no?