peterb

I've used Brasso for over 30 years, works well. Solvol is also good but a little more abrasive and costs more. Bye, PeterB.

Hi Biff, As shercoman said earlier, try the shift spring stop eccentric adjuster to see if you can get all of the gears with your new sheer pin (The spring with top hat looking shouldered washer with a pin across it). If not, then it is very likely to be just a shift fork or two, the older PRO's had shift forks that you could position back to back to check if the forks were parallel, later ones look more beefy and don't allow this visual check, pity as now it becomes difficult to tell which one or two is/are bent - look for suspicuous looking rub marks on the ends of the forks. You'll need a flywheel puller, leave the head on the barrel and remove as one unit, maybe a puller for the crank gear though if you do this right, you can leave it in place and try to split the cases leaving the gears and crankshaft in the RHS case, you can get away with leaving the k'start shaft in place but I find it better to remove it, don't lose the washer between the k'start shaft and the clutch case, leave the hydraulic connection on the clutch case, should take about an hour or so. Need a new c'case gasket and clutch gskt - check the c'case seals! Bye, Peter.

Hi Neo, If the motor was making a rumbling noise then it would be just the main bearings, usually a knocking noise from the bottom end, in time with the revs is the big end worn, maybe from the sand! For main bearings, there should be no end float and no discernable up and down play. I think you need to strip the motor down and take a look, you can leave the head on the barrel and remove as one unit. Press the con-rod to one side and try for up and down play, there should be none at all, try it at TDC. If main bearings, try the later sealed type, all seems very odd to me for mains to be completely sealed but by accounts on the forum, they appear to work, as Cope said, go for C3 clearence if you are not getting bearings from your Sherco supplier. Always replace the crank oil seals when pulling the motor down, use Sherco ones, usually high temp viton rather than std material. If you find play in the rod, you'll need a new rod/pin/bearing kit and some one with a press to split the crankshaft. Bye, PeterB.

Hi Spokerider, I run a 28mm Keihin flat slide (ex 300 Raga) on my 1978 Bultaco 325, all standard size jetting/needle except that I soldered up the main jet and drilled out to 1.00 mm. (Size 100) as I didn't have any small enough. This works very well with or without a reed valve intake on this bike. I usually fit a 26mm DellOrto PHBL 26 as jetted for a GG but with 95 main jet, for all the older Bult's and Ossa's. Haven't tried one on a Montesa yet but it should be fine. You must use an inline fuel filter with these carbs. Your pilot and needle are fine, not sure about the needle jet - try it out. Bye, PeterB.

Hi there, If you were going to ride in the woods a lot and generally go trail riding, the 321 is perfect for this. The 06 PRO is a far better bike for just trial riding. Bye, PeterB.

Hi camlifter, Try dumping the oil, 10W-40 would be too viscous, try either a mineral 10 weight or an ATF rated to Dexron III, 500ml. Bye, PeterB.

The same thing happened on my GG after 1 year. In my experience, the Iris chain does stretch fairly quickly compared, for example, to a DID 520 HD. Bye, PeterB.

Hi camlifter, The 06 model uses mineral oil as the operating liquid inbetween the clutch master and slave - just making sure you haven't used hydraulic type oil here. The main reasons for the clutch dragging would be the slave seals or master seals passing, or the system needing bleeding, or not having correct gearbox oil - I'd start there. For clutch packs that are a little high, you can get away with rubbing down the fibre plate on fine emery paper on a sheet of glass. It doesn't take much. The finger height seems low, I can't remember off hand the correct height (17.5 mm is it?), but anything less doesn't help. Bye, PeterB.

Hi Ian, As Ralph suggested, if the ding in the stanchon is not too bad, you can dress up the burr's with a fine stone and fill in the ding with araldite or similar. You may have scored the top bush too, worth a check. I don't think the 06 Beta had aluminium stanchons, don't they have Paioloi's with steel stanchons? Bye, PeterB.

Hi Tom, I prefer to use a GJH needle, gives a better response than the JJH for me. 122 main may well be ok for the 04 bike, for 06 onward a 126 or 128 is a better size as the motor runs lean with the (std) 122. 45 pilot is a bit rich, better with a 40 or 35. With a 45 pilot, the air screw needs to be out approx 2 turns. You must run these carbs with an in-line fuel filter as there is no filter on the carb, like the DellOrto. The Keihin has a larger diameter inlet stub but you can squeeze it into the existing rubber manifold, don't push it in all the way as the Keihin is shorter than the DellOrto and you'll find the airbox hose doesn't reach the carb properly. You can get jets and needles from Allen's in the UK - google it. You need a longer inner throttle cable with the Keihin, order one that fits the 370 model - can't remember the P/N but I think it ends with ...0003 Bye, PeterB.

Not all of the 520 chains interconnect very well, Iris for example, has a peculiar size pin (bound to get some jokes on this one) and I think you would really need to get a length of chain that is the same make as your present one to be sure that you can connect. If Shropshire is close to N.Wales, then there are a bunch of riders around Llanglochllen who tune in to TC who may be able to help - can't remember the district too well. Ta ta, PeterB.

Hi Nick, I checked the garage and do not have a full set of spokes for the older bikes. The spoke lengths are 202mm spkt side, and 197 disc side, 3.5mm dia. They are the same spokes for all GG trial models up to 1996. Bye, PeterB.

Hi EDGAS250, I remember you used to have an old Gasser. If it were me, I would strip out the forks so you can properly align each yoke (triple clamp) into a machine vice so you can accurately drill out a centre hole in the piece of bolt left in the yoke. Would be good if you could first get a small centre punch in to pop the centre - has to really be bang on. I wouldn't use an easi out as if this snaps inside the bolt then you would never get the bolt out. The bolt would be an M8x1.25, if you first use a pilot drill, say 3mm then a tapping drill, 6.8mm for M8, you could tap out the thread, effectively removing the broken bolt. I think you were from the Guisborough area, there should be a few riders around there who would have some short lengths of 520 chain that they would give you, try Allan Smith or Fothergill if they are still in the area, they would help. Bye, PeterB.

Ay up Nick, I most likely have a full set of spokes at home (NZ) for the old bikes and definately have a 1989 250 aire in the bike shed to measure the spoke length in case not, will have a look tomorrow and PM you. Ta ta, PeterB.

Hi MJB, These are always difficult ones to solve. I think the 05 model has the Ducati ign system. These work best with about 4 thou air gap between pick up sensor and flywheel. Also, check to see the LHS main bearing has not failed (up and down play) which would then allow the mag (flywheel) to perhaps touch the pick up sensor while rotating when heated up which could explain your symptoms. If you have changed the stator, then you would also have a new pick up coil. I can't remember, but is the Ducati voltage reg separate from the HT coil - I think it is. If so, can you try a friends HT coil. Another area to check is the reed valves, they can splinter at the ends. Also, check for dirt in all of the carb passages, remove the needle jet to blow this area out too. Lastly, the LHS crank seal may be leaking in air, perhaps more so as the motor heats up, particularly in the unusual Feb heat wave that you are experiencing. If this is leaking, then there may be tell tale signs of oil mist around the seal area behind the stator. Hope this helps, PeterB.

Hi Steve, I tried a 9/42 combination but this was way too low for me. The 10/44 feels much the same as an 06 with 10/42. I'm not 100% sure yet, but I think the different overall gearing may be due to the crank gear and clutch basket gearing being different to the 07 models, the crank gear on the 08 models has 27 teeth, I recall 28 teeth for the older model - but then this just doesn't work out - still to confirm. I used a pair of older style GG sst footrests that I cut and MIG'd 10mm lower at the mtg bracket area. I'm happy with the riding position now. Bye, PeterB.

Hi Glenn, I've run 300's with the Hebo flywheel weight for over 4 years now, never had any main bearing issues at all since the PRO came out in 02. I always use a mineral oil and change often. I chatted with Al the spanner up North recently regarding oil for the PRO, he has used a synthetic oil on the later bikes with success with regards to preventing the main bearings from premature failure - which occurs when the water pump seal/shaft fails and lads don't notice this soon enough, allowing the water to find it's way into the main bearing well, creating rust. Al has noticed that the synthetic oils are better than mineral in that they leave a more resilient film of lubricant on the bearing surfaces preventing water contamination. I still use a mineral oil though - old fashioned! Remember to tie back the rear brake hydraulic hose from the shock and to tie back the rear brake master cylinder reservoir pipe to prevent the shock spring from wearing these through for the SSDT. Bye, PeterB.

That's right, the latest Raga models are kown as an 08 Raga, with the new round tube frame. (Standard production models are known as 09 models) I have a 300 Raga, previously had an 06 Raga 300 and an 04 300 before that. This latest model has by far the most torquiest engine of my 300's. Carburation was lean and needed a larger main jet plus , for me, runs best with a GJH needle. I preferred the 06 model for riding feel, the 08 feels as though the footrests are a little high and quite a long ways back. The plastic triple clamp to frame protector restricts steering lock and feels much better with it removed. Gearing is higher than 06/07 models, even with a 10T gearbox spkt, but is just fine for me with a 10/44 combination and now feels like the 06 bike. I ended up making up a set of footrests that were 10mm lower and this feels a lot better. I fit the Hebo flywheel weight and this is great for riding up rocky creeks (becks, burns). As it is, the bike is bril and hard to improve upon, better than my 06 Raga even. By comparison, I had a ride on an new Evo 290, felt like riding a plank after the Raga with a heavy and on/off clutch action, still, other riders like them. Bye, PeterB.

Woops! Maybe I'll have to send him some kiwi stickers! Bye, PeterB.

Hello guys, I'm not in favour of tapping the shaft to knock the impellor to get the seal out, rather, carefully remove the seal from the inside but not with a screwdriver. When removing the outer brass looking bolt, be aware that there is a nylon washer to seal this bolt and then between this bolt and the shaft, there is a small sst shim that is easy to lose. There were several revisions of shaft material and surface finish over the years, but with a pump running at crank speed, it is difficult to prevent shaft and seal wear. Bye, PeterB.

Hi John, I turned up a piece of scrap steel that is a sliding fit into the bearing with a square shoulder that is used to drive against the aluminium spacer. The spacer is shouldered to fit inside the 6004 bearing. Heat the bearing housing up with boiling water first then drive the bearing out with the drift. Flick off the bearing seals and refill with water proof grease and refit the covers. Heat the housing to fit the new bearings. Bye, PeterB.

Thanks copemech, I've added this brilliant info to my list of engineering stuff. Bye, PeterB.

Hi Jon, I haven't heard of Redline Water Wetter - not since reading about it in these forums that is. If it is to reduce cavitation, as advised, then the physical characteristics of the addittive would be different to plain water, in effect to alter the vapour pressure of the liquid so that it would flash off at a higher (vacuum) pressure - vapour pressures are usually given in terms of psia, psi absolute. As far as the Redline Water Wetter working to improve thermal heat transfer, I can only guess that it has an improved thermal transfer over water - like metals, copper conducting heat better than steel. Bye, PeterB.

Had to add my tuppence worth here - more so for Stork really, I used to size up and specify Fisher control valves for various petrochemical fluid control applications, taking cavitation, or flashing into account as this can cause significant damage in the valve body and downstream piping. Cavitation occurs when a liquid changes state to a vapour state usually from an increase in fluid velocity at the point of or just downstream of the greatest flow restriction. At this point, the flow velocity is at it's greatest creating a substantial decrease in pressure which can drop below the vapour pressure of the liquid creating bubbles that tend to implode on the surrounding surfaces that causes significant surface damage. What a memory! I tend to use 100% coolant in my bikes, not adding any water. Bye, PeterB.

I was also thinking it may be more akin to the Don Smith Stag but I don't have a photo handy to refer it to. I think though the Stag would have had an earlier Montesa motor, the one in the photo looks like it is from a 348/349. Bye, PeterB.