raygrilli

So I ordered the GasGas part as it was cheaper…and it turned out to absolutely the right thing to have done The original Sherco switch and the new GasGas switch are identical parts in every way apart from one has a GasGas part number and the other has a Sherco part number. They are both normally open bimetallic switches that are 75degrees ‘on’ and 68degrees ‘off’. Threads are identical and are M16x1.0 as far as I can determine. GasGas part now fitted to my 2011 Sherco 2.9 and all is working exactly is it should do. See photos - the Sherco part is always on the RHS.

Is anyone able to tell me the thread size and switching temps on a 2013 onwards fan switch? Also, is it normally open or normally closed> I'm fairly certain they are interchangable with 2011onwards Sherco switched but need to confirm. Thanks Ray

The fan switch has packed up on my 2011 2.9. The thread size measure M16x1.0 and it's switching is marked as 75/68degrees (when it works, obviously!). The fan switch from a 2013 onwards GasGas may fit, but I can't 100% confirm whether they are interchangable. The GasGas unit is significantly cheaper to buy than the Sherco unit, even though they are at least 99% identical. I've spoken with the (slightly less than helpful) chap at TrialsUK who told me they are definitely not interchangable as the thread size and switch logic is different (but Sherco switch is normally open and he advised the GasGas switch is normally open, so almost certainly doesn't really know his onions!), but they are equally listed by trials breakers on Ebay as a common part. TrialsBreakers ebay listing (new part) https://www.ebay.co.uk/itm/233925021403?hash=item3677048edb:g:vpkAAOSwLzBe-4lX TrialsUK GasGas part https://www.trialsuk.co.uk/GasGas-Radiator-ThermostatFan-Switch---TXT-ProRacingFactoryGP---2013-Onwards?search=thermostat TrialsUK Sherco part https://www.trialsuk.co.uk/Sherco-ThermostatFan-Switch-2010-2017--Scorpa-SRTwenty-2011-2017?search=thermostat Any knowledge appreciated! Ray

Thought I'd share my new sidecar outfit. I made the chair as a close copy of a Rushton a colleague lent me that he uses with a Montesa. Tubing is 19mm x 1.6 and 25mm x 2.5mm. Chair wheel lead is 10.0''. Shock is from Falcon. Wheel hub is an unknown brand with 20mm ID bearings. Rim is 17'' x 1.2'm Honda Cub with tyre to suit. Brake is Hope. Swing arm is on nylon bushes and bronze sleeved shaft - thought I'd try without roller bearings and see how long it lasted...at least it won't seize with rust! Bike is a 2002 Gasgas 250 Pro. First outing last weekend was entertaining to say the least. Hope to do some club trials at Mansfield Maun and see how we get on...

Not sure about the quality of the cheaper ones, but I suppose you;ll get what you pay for. One thing to check though is whether you want it to be waterproof or not, the cheaper ones generally don;t have a waterproof fabric, so all that happens is the rain gets sliced up into a fine mist and everything inside just gets wet slowly!

Update! Right, messed about with changing the pilot jet for a richer one. This got the engine running so much better so was as tep in teh right direction. Engine still not perfect though. Soooo, gave up and have put a Keihin on it. It's the carb the previous owner had onthe bike with a 300cc barrel/piston instead of 272cc. This carb has transformed the bike. It runs so much better and is a lot easier to ride - it does what you expect when you open the throttle! No idea of jetting as I just threw it on and it worked. If I need to take it apart to clean it at some point I'll update with jetting specs. Used VHST anybody?! Ray

I have a 2011 2.9. I find exactly the same as you - my foot slips off the kickstart sometimes too. It doesn't help that they're bl00dy hardy to kick over in the first place. I just make sure I kick 'into' the bike as well as down, that way I slip off less often! Not much help, maybe, but my way round it.....

Made an interesting discovery after talking to Chris at Splatshop. The reeds in the engine are twin reeds, so as far as I can make out this means that they are probably Boyesen reeds and not the original ones (which would be a single reed petal on each side instead of the two reed petals per side that i have). Digging around the forum has enlightened me to the fact that Boyesen Reeds tend to cause the engine to run richer than with std reeds. Seems I've got my diagnosis right all along in thinking it's been running rich. So I've just received a U33 pilot jet from Splatshop which I will try in place of the existing S33 pilot jet. Apparently the U jets have larger air holes than the S jets so therefore give a leaner mixture for the same fuel orifice size. I'll fit it and let you know how it runs....

An update..... I think I'm close to having sorted the problem. Dropping the needle to lean the misture overall has made a massive improvement over the original setting of the needle in the middle circlip position. The final fix seems to be running the idle mixture very lean - only 1.5 turns out on the idle mixture screw. This has now corrected the poor low speed running, but I do now have a little bit of hunting on overrun as the engine comes back to idle. I think the final final fix will be to fit the only smaller pilot jet available, which is a 32 instead of the existing 33 jet, as this will hopefully allow me to run a little richer at idle so that the slight hunting is corrected, whilst allowing the mixture at small throttle openings to remain similar to the mixture with the current pilot jet/idle mixture screw settings. Reckon I'll hang on before buying a new Gas Gas with leaky brakes!! Ray

Thanks for the info. I have had the carb apart and cleaned it out thoroughly with compressed air when I checked the jets were the right ones. Cleaning it out didn't seem to make any difference, althoug I will do it again paying particular attention to the pilot drillings. The issue is, to be honest, a pretty subtle one now that I've dropped the needle. The engine is just lacking urgency at low engine speeds. I suppose there is a chance that there is an air leak between the carb and the crankcase - I'll spray some carb cleaner around there when I've got the engine running to see if it makes a noticeable difference to how the engine runs. Maybe it's an issue with the reeds??? Although I don't know much about the effect of reed problems on engine running. Thing is, I've dropped the needle to make the engine run leaner which has made a marked improvement to the way the engine runs at low speeds with small throttle openings, this is why I think that I may need to go down a size on the pilot jet, although no-one has yet suggested that this may be a solution to the problem????? But, Splatshop only list a 32 pilot as the smallest available and it's got a 33 in at the moment, would going down 1 size make a discernable difference? Hmm...

Cheers for the info so far but I think i really need to understand what to do with the pilot jet sizing to fix the problem. I'm running 80:1 mix and this was fine in my 2002 GasGas, so fairly certain it's not that. Also, I can't run the bike up the road as it's not road-going! I can't completely get my head around the idle mixture adjustment either - does unscrewing the mixture screw (not the slide stop!) (i.e. turning clockwise) incease the amount of fuel, or is it an air circuit that by unscrewing increases the amount of air? I know this has only a very small effect on low speed running - 0 to 1/8 throttle, but it does have an effect, and if I understand what the adjustment controls it might help me understand how to fix the problem! Ta, Ray

Hi All, I hope collective wisdom and experience can help me sort out a fuelling issue I have with my 2011 2.9. As received from the previous owner the engine was often 'bogging' quite badly, and on a number of occasions would hunt when engine speed came back to idle. A few fellow riders suggested to'clean it out' by revving the guts out of it for a few secconds before starting a section, and this did seem to help, but in longer sections the bogging would start to re-occur. So, I checked the carb setting were as per Splatshops' recomendations :- https://www.splatshop.co.uk/2010-2011-sherco-preparation, and it seems that the 2.5mm restrictor in the fuel inlet to the carb was missing and also the float height was at 21mm whereas it should have been 18.5mm with the 250 jet that is fitted. After taking the bike out again nothing seemed to have changed, so I had a fiddle with the needle height to see if it would make a difference. Splatshop spec for needle height says middle groove on needle with washer placed nearer to nut. This is what I had as received. I had a go at lifting the needle to see if richening would help, and it made the bogging worse. Dropping the needle seems to be the best improvement I can make, and currently I have the circlip in the top groove with the washer between the circlip and the main slide itself, which seems to be the best I can get it. The fuelling is still not right though and the bike is still sluggish from low engine speed compared to a 2.5 of the same year (although this was Luke Walker's bike and he told me he'd changed the carb from the original to make it run right!). The hunting at idle is no longer happening. Also, with the needle set at any height the engine is fine for medium to high speed running. Can anybody shed any light on how to improve the fuelling from this current condition? I'm not that familiar with fiddling with carbs and not certain what to try. I 'think' that changing the pilot jet would probably be the next thing to do, and perhaps fitting a smaller one to lean out the low speed running and perhaps lift the needle back up again, but not really sure. I've spoken with Chris at Splatshop, who has been very helpful, but he's on hol this week and i'd like to get this sorted sooner rather than later.... Any knowledge/thoughts/experience would be greatly appreciated. Cheers, Ray

I had my barrel replated by the place in Weston-Super-Mare (Langcourts??) about a year ago. I supplied the new piston to them and they plated/honed the barrel to suit. They even charged a bit less than the told me on the phone and think it cost about

Thanks for that, all makes sense now. I'll wait for the log book to turn up and then get straight onto sorting out a SORN in my name.....

Hi Chaps. I wonder if anyone can shed any light on my SORN situation? I've just bought a bike that was SORN'd by the previous owner. When we filled out the V5 for change of ownership I'm pretty certain that he ticked the 'currently SORN'd' box. My question is, do I need to do anything to keep it SORN'd (I'm not going to use it on the road)? And, how do I know that the DVLA will not fine me or do something else horrible to me if I've not filled out a SORN form as the new owner if that was what I'm supposed to do?? The DVLA website isn't that helpful in clarifying my situation, so hopefully collective knowledge/experience will be able to help me out?! Cheers, Ray

Thanks for that - looks like what I'll be needing. Looking at your avatar, the Aprilia 50 is the same as your Fantic 50, but with a different tank and seat. Is it possible to get parts for these bikes still - if so, where do you get them from? Also, we've been thinking of putting an oversized barrel kit on it for years as it's not very powerful at all. I've searched the net but can only find a Swedish (?) company that does 70cc kits, but they are very expensive. Thanks, Ray

I have an old Aprilia 50cc trials bike from the early 80s that I need to find a rear tyre for. The bike has been in Italy for the last 25years - we used to ride it whist on holidays there - and I'm bringing it over to England to give it the maintenance it has long been needing. The original tyre was removed a few years ago because it split and is now lost, so I don't know the size of it. The tyre fitted at the moment is a 3.00-18 trail type tyre which is rubbish, so I need to find a new tyre for the bike. I've had a search and can't seem to find any details about tyres that aren't 4.00-18, as fitted to adult sized bikes, but I think these will be too wide to fit within the swingarm; so can anyone shed any light on a proper trials tyre that may be available in the UK that is narrower than 4.00-18 but wider than 3.00-18? Thanks, Ray

Thanks for that. I suppose what I really should have said was that when warm the lever travel for engagement is much shorter since the clutch is not dragging in the same way as when cold, meaning that you pull away with the lever further from the bars (if you see what I mean?). Ray

Just another bit of info: The clutch on my 2002 250Pro drags mauch more when cold than warm, and also the engagement point moves further from the bars as the oil warms up. This is with a brand new (10hr or so use) clutch pack at 9.85mm thickness and the clutch fingers at 17mm as per the GasGas spec - oh, and also with a 9.5mm master cylinder and Dextron 3 ATF. I have managed to get it set up so that a single finger can comfortably disengage the clutch against the other fingers. I've also found that drag is significantly worse in first gear than higher gears, and increasing idle speed a little helps address the risk of stalling. Ray

Well, I've now stripped and rebuilt the m/c. The seals and the bore look absolutely fine, but there was a bit if dirt/swarf on the main pressure seal as i took the piston out, so I've put it all back together clean and I'm now attampting to store it deisengaged to see what happens. If it works then I'll have another go at storing it engaged and see what happens. Many thanks for the advice. Ray

Thanks for the info. I've put new orings in he slave cyclinder, so without replacing the engine side plate and top hat slave cylinder there's not much more I can do at that end of the system (Bike is a Gas Gas 2002 250 Pro). As for the m/c, I do know that something there is not in good condition as it does weep hydralic fluid out past the piston during a day of usage. May well take the m/c apart and see if there's anything obvious there, but the problem is - to get air in at rest then I have to have two leaks I reckon, one for fluid to get out and another for air to get in. All a bit confusing to be honest and I don't want to really start throwing expensive new bits at the bike unless I'm at least a little confident they might fix it....

I have an ongoing problem where the clutch system gets air in it when stored. This happens even in 24hours to an extent where the clutch needs bleeding before it will disengage properly. I spoke to the helpful chap at gas gas uk and he advised that i should store the bike with the clutch system pressurised to ensure that the seals are under pressure and therefore sealing properly. This sounds like ii might work, but haven't tried it yet. Does anyone have any experience of doing this - wondering if long term it will cause any problems. Cheers, Ray

Cheers for that. That's a completely different routing to mine at the moment (just got the bike). My hose currently goes straight down parallel to the brake pedal push rod and then takes a very awkward curve between brake pedal and swing arm. I'll se if i can get mine to take your route as it looks much better. Cheers, Ray

I've just removed and replaced the engine in my 2002 250 Pro and I'm not sure I've got the brake hose routing correct where it comes out of the master cylinder and bends round to go through the swing arm. Should the hose go from the master cylinder and then wrap underneath the brake pedal before moving inboard and going into the swing arm, or should the hose come down from the m/c and then wrap around inboard of the brake pedal and then go into the swing arm? I've currently got it running with the later of these two options as this is the only one I seem to able to get the hose to achieve, but it causes the hose to be slightly sandwiched beteen the pedal and the swing arm at full rear suspension droop, which will either potentially sqaush the hose or put the rear brake on when I'm not expecting it. If possible would someone mind taking a look at their bike and let me know which way the hose goes, or maybe even try and get a shot of how it is so that I can hopefully get my routing correct. Cheers, Ray Grilli