clav3

I've owned a 2015 Factory 300 for a few months now and I'm really enjoying it. The bike was tuned way too lean from factory in the mids and too rich on the pilot. Main was spot on. I have a 40 pilot one turn out, JFH needle 2nd clip from the top, the standard 4 slide and 128 main. The JFH needle is simply an extension of the JJH. These bike are a hand full with instant power straight up. I have a slow action throttle on mine now to give me more scope for slow off camber loose ground but as soon as the throttle is cracked you can climb a tree. The problems I have had are a pinhole in the exhaust ( a problem from exhaust manufacturers ) Airbox Sherco stickers coming off from new. LED's in the headlight not working. I know no one uses them but they should work. Squealing Fan. All these problems have been promptly rectified on warranty by the importer and Sherco. If I would have ridden my bike like an expert with the tuning it had from new it would have had overheating issues also. The first ride was difficult while trying to run in up a small hillclimb and I could feel it was really lean in the mids so I nursed it along until I tuned more fuel into it. If you just keep twisting the throttle and expect it to be all good when it's trying to tell you it's not, well ???? Lastly it is a Factory Bike and the clear power of it confirms that. High compression is a part that. I can't believe the mine's the only one running well. ( Looks good too!) I must say that I would like to fix that typical Keihin just off throttle blubber after bouncing at downhill angles but it's a small price for such a great bike.

Unfortunate but don't expect any service from Sherco. A few years ago I had to replace vulcanised rubber parts in my front forks. Sherco refused to reply to my emails.( There were no part numbers in the parts books. As if they didn't exist) The importer here in Aus eventually got me in touch with Paioli and even though the process was difficult with the language barrier they eventually agreed to sell me the parts I needed. I think it may be a Spanish thing. I'm keen to buy one of these bikes since there has been no dramatic changes for a few years and small issues seem to have been worked out. I agree they shouldn't be that much different from the standard bikes and despite the advertising a far cry from Cabestany's.

Haven't looked at new bikes for a long time. Does the 2014 and 2015 Factory have dual mapping?

I've have used Motorex 10w30 and found it very grabby. Have found (if your clutch is in good condition) a good quality mineral or semi synthetic 15w50 gets rid of nearly all clutch shudder and grabbiness also makes the clutch super progressive. If you use a low quality one you can get some clutch slip. I have been using shell AX7 15w50 semi synthetic but is getting very hard to find so I've just started using Motul 3100 gold 15w50 mineral which after 1 ride seems even better and still hooks the clutch up in high gears uphill full throttle. But will see how it performs after a few rides. The thicker oil also stops that Sherco clutch grab from cold.

I sent my cylinder to Victoria to Electrosil to be re plated and sized to new piston after trying many different ideas such as different carb (Keihin), new reeds, and original lower compression head. Also another plating company giving the cylinder a light hone to straighten slightly, none of this worked. It only took 3 days to get my cylinder back from Electrosil. Put it all back together and its all fixed. No noise except the purr of a very tight and quiet sherco engine. The cylinder only had 0.4 thou variation from bottom to top and even with piston tolerance of 1.1 thou at the tightest point, somehow the variation was enough to cause a very bad piston rattle at mid to high revs. No one thought that this was really going to fix it, but at even more expense, it was the right move. I hope this thread can help some other poor bugger, with his head nearly completely done in one day Thanks all.

Today I checked the timing on my mates 2012 300 Cabestany and seemed to show that while the mapping is different on the bikes, my bikes timing seems to be okay. This also confirmed that sometimes the switch is the opposite way round since the timing light shows my map 2 to be more advanced and map 1 on the Cab to be more advanced. My mapping shows a 7 to 9 mm difference (measured on the case) at idle and only about 3mm diference at higher revs and nearly no difference when screaming. (I checked the timing when the bike was only about a year old,and running fine, and this has not changed.) While my mates Cab shows no change at idle but at higher revs, a big difference and the more you rev the bigger the difference. This test also shows the at higher revs these bikes can run sweet at a variety of timing settings as long as they advance up to at least 3.5mm BTDC at higher revs. Oh well, tomorrow I'll pull the cylinder off again to see if I can sought out this knock.

New stator in and no difference. I ran a little test with a timing light though. I now have a TDC mark and 3.5 mm BTDC mark on the case.(the 3.5 mark is where the factory mark on the flywheel lines up with using either stator, at about 1/2 throttle on map 2, which is the more advanced map.) I held the revs at exactly where the noise just begins and flicked the mapping switch back and forth from map 1 to 2 consecutively. The timing light showed the noise started at about 3mm BTDC on map 2, then switching to map 1 the timing light showed about 2mm BTDC. So held at the same revs the timing jumps back and forth but the noise remains stable at just audible. This seems to prove that the noise is not timing related, but rev related. I was thinking maybe the CDI was at fault but after doing the above test I think it would be pointless. It seems to occur at the same revs wheather free reving, under load or riding down hill with the clutch out. Probably going to try another piston or the old one. Dunno.

2008 290 dellorto. 33 pilot 2.5 turns out and still reasonably rich down low. I know you're probably sitting there thinking this guy doesn't know what he's talking about putting a 33 pilot in but three facts come to mind. 1. Bike has run sweet as for about 4 years with this carb setup. 2. Engine knock comes in above 1/3 throttle. 3. I have already tried lifting the needle to the max but no difference. Forgive me Copey I know you,re trying to help but you need to get your head around the fact that not all 290 Shercos require the same jetting. I've only owned two and my old one was set up much like yours but this one does not need a 38 or 35 pilot. Today I spoke to a small engines mech that works on an ex Aus champs bikes and he had no doubt that the bike has a timing problem. He had seen the exact thing before. That bike started fine, runs smooth down low but as you increase the revs, hey presto, engine knock. On that bike, on the factory setting it dialed at 1.5 mm BTDC so he retarded the crap out of it with the same results, engine knock at higher revs. Put a new stator on and fixed. He told me to dial gauge mine and 3.5 mm BTDC was the go. I have another stator to try so we'll see. Don't worry I'm not getting my hopes too high just yet.

Have done a second rebuild... so, new main bearings and seals , piston and rings ( within suggested tolerances of 1.06 to 1.27 thou) with the variation in the bore of 0.2 to 0.3 thou, new conrod kit including all top and bottom end bearings, new clutch basket silent blocks rivets and plate, no sings of anything touching hitting or rubbing on inspection. The engine is pristine. The cylinder could be re- coated to make it brand new again but I don't know if that will get rid of this persistent noise. The noise is the same as it was before the second rebuild. I have also added another 0.5 mm base gasket, squish is now 1.3 mm...made no difference. I've put a timing light on it and the timing advances about 18 to 20 mm as it gets to about half throttle. Does anyone know if this sound about right? Just a note, the engine is running super smooth and is reving up normally, just has a horrible noise as it revs up. I'm thinking of borrowing someones electrics to see if thats the problem. I must say I'm getting a bit over it. Not sure how to get a video up for anyone to listen.

A few of us have ridden our mates new 300 Cabestany and all find it rediculously smooth and easy to ride, even a few statements of " the easiest bike to ride I've ever been on." We have a variety to try, 2 stroke and 4 stroke Betas, a couple of 2011 Ragas, a couple of 2012 Ossas, 2001 320 GasGas.... I found it very smooth for alot more of the start of the throttle range compared to my 2008 290 but when you crack it you really feel that 300 cc touque. The owner is a C grade rider and he still has his old 2009 4 stroke Sherco which he strugled with a bit despite gearing it down. He finds the new Cab alot easier to ride.

Did check the con rod for wear and have done several times since using different methods and virtually impossible to feel any verticle movement at all. Thats why it was left alone especially at a cool $405 AU Also checked by a guy who rebuilds engines of all types every day and is a long time trials rider. The wear doesn't just happen over night, and I'm fairly sure it's at the start of being loose and thats why it's only making a noise above 1/3 throttle. I can tell you that it's left us all scratching our heads. But the only thing left to replace is the bottom. It is a 290 and since checked the squish. At the sides 35 to 36 thou which is about 0.9 mm. Splat shop suggests 1.2 mm but the dealer here in aus suggests between 0.8 mm to 1.0 mm. Anyway I received the parts today and there is a big difference in the side to side movement at the top of the rod. So anyone reading this who wants to know what that might be, its no more than 0.25mm side to side if that, at the top with the bottom held in place. My old one was about 1 mm more. Neither feel any up and down. I'll stick it in and let anyone with any interest know what happens. Thanks for all the input.

Only one Base gasket from new. The dealer here suggests only the standard which is what I've used before. The engine rattle is definetely not fuel related! It is engine rattle not pinging. I must say I cannot remember the engine running this quiet before, which may accentuate the noise coming in at higher rpm. Main bearing and seals are new, new piston and rings with correct tolerences. Even checked the crank with dial gauge and blocks. The crank felt okay but wasn't checked until it was fully removed from the engine. It's sought of like there is only slight wear but enough to cause a noise at higher rpm. Thoughts on this theory? Probably not a good idea to check squish if the bearing at the crank has slight movement. I have taken the head off and rotate the flywheel until the is about 10 to 15 mm from top, push down sharply but gently and the piston drops slightly and makes a tick noise. Dropping slightly, I mean barely visible by eye. It seems the conrod bearing should be replaced. (Conrod kit)

Done another engine rebuild and engine runs realy quiet. As I increase the revs to about 1/3 throttle I hear an engine knock like piston hitting the head, not real bad but annoying. So I've had a few lite hours of run in time. I've taken the head off and inspected but no visable marks on the head or piston. The only thing we didn't replace was the conrod assembly. As I push down on top of the piston there is a slight tick noise like the bottom crank bearing needs replacing. When the engine was rebuilt I have only ever replaced the base gasket with a standard one but I have just read on the splat shop web site that the standard base gasket is now 0.5 mm thick and they recommend a squish clearance of 1.2 mm and I may have to use two base gaskets to achieve the correct squish. I have never checked the squish, just replaced with a standard base gasket. We have to pull the engine apart again to fix this knocking sound but not sure whether base gaskets alone will fix the problem. Any advice on Base gaskets or crank assembly replacment appreciated.

I know this is a bit of a dumb one but does any one know which way round the clutch pushrod goes in a 2008 sherco. Smaller rebate to the slave side or clutch plate side. Thanks.

The right side diag is upside down. That's how it was sent to me. But if you look real close you'll see a small recess that the rubber washer just pops into. I think it acts as a bottom out bumper for the plunger. It also may slow or stop the oil flow from the top of the plunger... not sure? Like I said the language barrier made it difficult to get much other info on the parts. I can understand how the vulcanized rubber to metal top out washer in the left fork wore out, but not too sure how the damper side washer in the right fork ended up split in half. If anyone out there is hearing a top-out clunk while pulling up on their bars, they'll probably need to replace the vulcanized washer. If you look in the parts book you may get this part together with the "pump group". I wasn't going to puchase the pump group and risk not getting the part I needed.