peterb

Hi Bartje, All of Jon's advice is great, I'll just add my experience on these, assuming you have already tried the eccentric adjustment. 1) It may well be just the top hat shaped piece that is under the gear shift return spring has rotated it's two parts out of alignment, check to see the spring separator tab is in the same plane as the cross piece in the top of the top hat - you'll see what I mean when you strip it out. If not in alignment then the two parts that make up the top hat have rotated and need to be re-aligned then brazed up - or better still - fit a new top hat with spring attached. 2) If the top hat is looking good, then the problem is more sinister, most likely to be a bent selector fork or 3. If you do need to go this far, check the forks back to back to see if they are square, any bowing will then show up. New ones needed. Also, on the early 02 models, the selector drum was heavily machined out resulting in the material between the tracks to be too thin, these sometimes collapsed giving rise to the symptoms that you have. (sorry!) Newer drums were fine. I just re-looked at the original post - it is a PRO 280 isn't it? Not the edition 280. Ta ta, PeterB.

Hi copemech, Thanks for the kind words. Most carbs run jet sizes as mm bore sizes, eg: 122 main jet is 1.22mm diameter, 95 is a 0.95mm dia. Pilot jets are the same (most carbs) so a 35 pilot is 0.35mm diameter. On the taper reamer that I use, it is calibrated in scfh propane gas, but has another almost linear scale that I use as a guide for boring main jets. I use two sizes, say a 118 and 122 and determine the difference on the scale then use this difference to relate to how much to bore out to. Anyway, it works. Ta ta, PeterB.

Hi straycollie2, The tanged plate you describe sits on top of the needle/clip and is fitted after the throttle cable is positioned, it is there to prevent the needle coming out of position and to prevent the t'cable nipple from springing out, the tang usually sits down into the t'cable groove inside the slide. Bye, PeterB.

Hi Kevin J, Araldite is a 2 part epoxy glue available in 24 hour or 5 minute cure. One part is a liquid epoxy resin, the other is tertiary amine (the hardener) used in equal amounts. It's been around for many years in the UK, NZ and Australia - probably sold under other names in other parts of the world. I have used it for fixing pin holes in crankcases on Villiers motors (I were just a lad) over 30 years ago and all sorts of other difficult fixes, including fork tubes (stanchons) It works well for a long time. It's not a plastic metal type of mix, more of a glue. Araldite was used on the Alta Suzuki that Mart Lampkin rode for a while when he was a bit younger and was used on aircraft. Jon's point of using a bit of barstock is good engineering practice, remember to use emery paper/cloth rather than sand paper as particles of the sandpaper "grit" can get left behind in the steel and create scoring. Emery is usually aluminium oxide based. Bye, PeterB.

Hi copemech, Thanks for the friendly comments! Never been called a ratchet head before - I'm sure my next phone call from a trials friendly rider will start with hey ratchet head! Anyway, I've been riding for a few years now so am a bit old fashioned and like to be precise with my (bike) carb set up, I do tend to run with the pilot a little richer than most but then still use a 35 on the Keihin (on a Raga 300). The GJH needle is definately the best for riders wanting a progressive feel in the way their motor picks up from low revs. The JJH works ok, probably has a quicker response but not as good (for me) as the GJH. The GG Ragas up to 2008 arrive with 122 mains and a JJH, they all ping at mid revs, too lean. I bore out the main to approx 126 which fixes the problem and the motor runs way out at the top end without any spluttering. Std reed v/v's. (I have a graduated long taper reamer used for boring LPG jets in the regulator business - courtesy of Fisher Controls Iowa that I have used for a few years to experiment with main jet sizing). I find that younger lads aren't so fussy with carb set up or even have a well oiled throttle tube and use skills in other areas for sections, lots of stop start clutch stuff. Ta ta, PeterB.

Hi there, bashplates are usually made from an aluminium allow which is probably heat treated to T5 or T6. In my experience, they are more than difficult to straighten out. Years back I tried to re-shape the plate from a 305 Fantic with a sledge hammer on the lawn, I think I managed to bend it just a little. Do not heat up the plate as you would lose the temper. If unable to straighten out, just try re-fitting with the front bolts in half way then compress the rear on with a G-clamp or similar. Bye, PeterB.

Hi there, Hey, I was in the Guisborough club too, few years ago! I forgot about the seat bit. I have the same plastics on a 1989 air cooled GG 250 and the once blue seat has gone to mush over the years. I scraped the stuff off, cleaned up the plastic with a knife and stuck a mid 90's GG seat sticker in place, looks ok. Bye, PeterB.

I don't know if you get this stuff in the UK, but I've used Jiff (a liquid bathroom scourer) with a green plastic scrubber, by 3M, on white plastics which worked really well. Bye, PeterB.

Hi Steve, This has a Kokusan ign system and these rarely go wrong. The HT cap may need to be removed, cut off 10mm of HT lead and screw back on, just to rule this out as a problem. Less than 5 kicks is the norm for hot/cold start. From cold, I always lay the bike down to the left to flood the carb. Could be a dirty carb, completely strip the jets and the emulsion tube (needle jet) then blow out all passage ways. Check float arms are parallel to the carb bowl mating surface when carb upside down. Check fuel is getting through fuel tap. Change the coolant, I use 100% anti freeze for the PRO. Does the plug get wet - is it water or petrol? Loud whirring may be std feature of your bike, it isn't usual for these. Check the clutch centre bush has not worn. Some had rather excessive clutch rattle, problem with having very thin, straight cut primary gears. There are two different lengths of spoke on the rear wheel, check out which length goes where. Assemble spoke/nipple with water proof grease. Hope this helps, bye, PeterB.

Well, I had a brand new RL250 when they first came out in the UK, after a few years of riding Bultaco's, I think it was either 1976 or 1977. Was a light bike at the time, petrol tank split at the rear, cases very thin, lots of backlash in the gears, did not grip well and did not handle well over rocks. Not enough power low down for me, was better with a very thin head gasket and a little more ign advance. Was pretty awful really. I tried to make it go like a Bult, but after 6 months of trying, sold it off and bought another 325 Bultaco. Having said that, there is an RL250 out here in NZ, owned from new that does go well but still has those handling problems. It has proven to be very reliable over the years. Bye, PeterB.

Hi Jan, The 02 cover will fit. The slave cylinder of the 02 operates with hydraulic oil but you may be able to change the 2 O ring seals for Mineral oil compatible types. Problem with the 02 cover is that these flex under clutch actuation and don't provide a positive enough clutch feel at the lever. The 03 onwards covers were improved to prevent casing flex. Best solution really is to replace the cover with a new one. The case is too thin for a weld repair, and quite tricky to weld in the kiskstart shaft bush area. Bye, PeterB.

Hi hewson, best to measure the piston/bore clearence in the area above the ex port and directly opposite to see what clearence you have. Should be around 2.5 to 3 thou. If you are short of a 325 piston, the Gas Gas 321 piston kit may fit - I haven't tried this yet - but the original Mahle pistons were from the same casting, only machined to a slightly different diameter, gudgeon pin is the same diameter (From memory, 83.2 for the Bult and 83.4 for GG). Could be a problem with the inlet port height as the GG pistons may have a cut away. It's worth a look in case you are unable to locate another Bultaco piston. Also, GG now supply S3 pistons for the 321's, need further investigation to see if these can be used on the Bult. From the descriptions, it does seem as though you may have too much piston/bore clearence. Bye, PeterB.

Hello sherpa (Tenzing!), A dragging clutch can be the result of a number of problems, master cylinder, as described by laser1, slave seals leaking, water in the gearbox oil causing the plates to swell, wrong gearbox oil (or contaminated oil caused by a leaking water pump seal) and swollen fibre plates. For 2005, the clutch actuation fluid was changed to mineral oil from hydraulic oil, have you been topping up with the correct fluid? Was the seal kit correct for mineral oil? Use an ATF oil rated to Dexron III in the gearbox. Check the clutch pack height with a caliper, should be 9.75 - 9.85mm, more importantly check the clutch finger actuation height (with the bike laid over to the left) should be a minimum of 17mm measured to the clutch centre. My guess is the slave seals are passing and maybe there is mineral oil mixed with Hydraulic oil. Bye, PeterB.

Hi Tazman, I know what you mean about those Duke's, you needed an arm like Arnie's to pull in those clutches. Most riding in sections is performed with the use of the clutch these days, you'll probably notice a finger hovering over the clutch lever on most riders so an easy action is almost mandatory. Bye, PeterB.

Hi there, I don't know of another motor that would fit in the frame and think it would probably be best to sell off the bike and get another model with gears. As far as I know, the "Boy" motor is made by Gas Gas. Bye, PeterB.

Hi there, I just pulled a spring out from a 1995 330 motor, spring free length is 37mm, wire diameter is 2mm. The clutch action on these older bikes was always pretty heavy (compared to the later PRO's) I did experiment with using 4 of the 6 springs, about 13 years ago. This worked ok in sections but the clutch started to slip on 4th gear blasts. Bye, PeterB.

Hi Roberto, What you describe, as Tim said, is quite normal for this particular motor. There is quite a clunk between 4th and fifth and this is nothing to be alarmed about. 1st through 4th is a little notchy I guess, but the gear lever should certainly return smoothly. Bye, PeterB.

Hi tombo, The standard pads are fine which were Galfers on previous models to 08, can't say for 08 at this point in time. Bye, PeterB.

The up to date news on the forks for the Raga replicas is that the 250/280 models have Marzocchi's while the 300 is supposed to have the Sachs/GG fork. Bye, PeterB.

Hi DFW, Usually caused by moisture in the carb, water getting in and not being cleaned out. Completely strip out the carb, totally, scrape off residue where you can and blow out the passageways. Bye, PeterB.

Hello Penno, As mentioned - check the engine mount bolts first. Other possibilities are the clutch centre bolt loose, or the flywheel nut (not so likely as the flywheel would be off by now) or if none of these then the main bearings may have worn, check for any end float and up and down play at either end of the crank shaft. Bye, PeterB.

Hi WrinkleyP, As Dave said, these are an easy peasy bike to work on. I never heard of a main bearing cage collapse before, wonder where it was made! Maybe the previous owner had the motor flooded with water at some stage and did not flush out soon enough which may have set the rot in. If you are hesitant about tackling the motor, try BetaPete (at least I think that's his alias) on the forums here, he lives in Guisborough (up toward Middlesbrough way) or for sure, Al the spanner at Derek Whites in Darlington would be more than capable too. Ta ta, PeterB.

Hi there, I'm not too sure what part of the exhaust system you are referring to. Do you mean the middle silencer box, top bracket? Whatever bracket it is, it is most likely cracking due to being stressed in the bolted up position. Fit up the silencer to the frame and see if all the mounting holes line up without being forced into position, if not lining up correctly, then file/drill or bend till the bracket holes all line up. Bye, PeterB.

Ah the joys of parenthood, I remember the first five years were the worst, hardly got a single full night's sleep at all, decided then that one child was enough! Bye, PeterB.

Hi Steve, I wouldn't worry too much about the carb rattle. I have used Keihins on Gas Gas since 2001 and after a while the rattle does develop, at low rpm just on tick over. It was evident on my friends bikes too and certainly not caused by a lack of airbox maintenance. I think there is little surface bearing area in the first few mm of the throttle body venturi of the flat slide Keihin when compared to (the force!) a circular throttle body type which may accentuate any slight wear in the area creating the rattle. If you have a close look, you can move the slide around rather easily back and forth in the throttle body in the almost closed position. Ta ta, PeterB.