aussiechris

Good luck with that !!! Honda/Montesa don't supply a rod kit as a spare part. They expect you to buy the entire crankshaft assembly for some hideous amount of money. I recently replaced the rod on my 260 4RT and used a rod kit from Hot Rods in the USA. Fortunately it is the same rod as a Honda CRF 250X or R (04 to 08). The Hot Rods part number is 8616 and the dimensions are - centre to centre 90mm, small end bore 16mm, big end bore 38mm, small end width 15mm, big end width 17.8mm, pin diameter 30mm, pin length 52.85mm, big end bearing 30 x 38 x 18mm, side thrust washers 1mm. The rod kit includes big end pin, big end bearing, and thrust washers but not the piston pin or clips. It is stronger than original (slightly heavier but runs smooth). Photo shows the original rod on the left. Parts with KRN on them (or KRN in the middle of the part number) come from a CRF250. Hope that helps.

All the guys I ride with run 100:1 (usually Motul 800 full synth) in modern liquid cooled bikes and have been for the past 15 years or so. And most of our bikes are between 5 and 10 years old now with no oil related problems. On the odd occasion we've pulled an engine down, there is tons of oil on the piston/crank etc. Feel free to run richer mixtures for peace of mind but I am yet to see any evidence that 100:1 has caused any premature wear or issue. And replacing or repacking clogged mufflers is a hassle I'd rather put off as long as possible.

If it is a crank seal, you should notice the bike consuming gear box oil. When my pro did crank seals recently, I was adding about 50ml of gear oil to bring the level back to half way up the sight glass for every tank of fuel. New seals/bearings and it no longer smokes or uses gear oil.

It's the map switch. Large button selects normal ignition map for dry conditions, pressing the small button selects a softer map for wet conditions. But in my opinion it's makes little difference.

Also check the primary (clutch) cover gasket after removing the skid plate. It's possible for the cover to get moved slightly on impact thereby breaking or dislodging the gasket.

Thanks Oz. I don't know who makes the Race Tech bushes, I assumed they were their own aftermarket jobs. If that was the case I would be happy to try them. However, I have not managed to find a dealer who could supply the Race Tech parts for reasonable postage rates or at all. I have tried to register on the Race Tech site so I could order them directly but something broke and I'm now locked out. Emails to both info@racetech.com and distsales@racetech.com (overseas sales) have gone unanswered. In desperation, I have ordered a pair of bushes and seals from the Splat Shop in the UK. They were showing the bushes under the old Honda part number so I thought I'd take a chance on them. They'll be another week or two away. The new bush and seal I installed the other week only lasted one ride. That same fork is leaking again but not too bad. I have a competition this weekend so it will have to do. Assuming it is a manufacturing fault (and I think it is), it's unfortunate that there appears no way for dealers or customers to tell if new stock is good or bad. The dealer seemed to indicate that the factory are just saying it's not a warranty issue. But I'm sure we're all happy to pay for new bushes ourselves but would like some certainty that they are good ones. I'll also be checking the fork tube to ensure it's not bent next time it's apart. But it was sliding freely last time I re-built it. The teflon just doesn't seem to be stuck properly to the metal. I've had numerous bikes with huge mileage and never had a problem like this - and never gone close to even wearing out a bush. Other than that, the bike is great. And I still think nothing comes close to the Showa suspension both front and rear.

That's top information - exactly what I was looking for. Thank you Sportsawyer. Those dimensions look correct. I see Race Tech also have the correct original NOK BR 2722 seals 39 x 52 x11mm (Race Tech FSOS 39 P) My new Montesa bush and seal arrived in the mail today so I will install those now. However, I will be trying to source the Race Tech parts (just need them to post to Australia) over the coming weeks because I'm sure the Montesa ones will fail soon enough. I see the Splat Shop are showing the older 51414-NN3-821 part in stock as well. It's disappointing that even the replacement bushes supplied to the dealers are faulty. The more correct course of action would be for Montesa to get back to Showa and get them to sort it out. .

Hi folks, I was wondering if anyone has found a suitable replacement top bush for the Showa 39mm forks. I am gathering quite a collection of faulty bushes as each replacement one I buy fails in the same manner (teflon pealing off and getting under the seal). The last one I bought lasted just one month (3 rides) and I'm getting quite annoyed about having to replace the bush and seal this often. I was hoping to find an aftermarket replacement or something off another bike. The dealer here has contacted the factory about this a number of times and they continue to deny the problem and just say it's not a warranty issue. I don't want warranty, I just want a bush that lasts like it should. Some of my bushes:

Yeah, anyone know why Jim is banned? He has done more to help Gas Gas owners than everyone else put together and as far as I know has never asked for anything in return or tried to promote his or any other business. Very disappointing news.

Hi Jim, You mentioned you only use XGF main bearings now. Are they the same a Xiu Engineering? The reason for asking is that 18 months ago I replaced the main bearings in my 2011 300 Raga (due to cracked crankcases) and I was talked into using the Xiu Engineering ones because they are lower friction and have long-life silicone seals. There was nothing wrong with the original bearings. Now I'm regretting that decision because my bike is consuming gearbox oil at an alarming rate and there are no external leaks. So it's looking like I will be tearing it down again and paying for yet another set of mains along with all the gaskets. If XGF is different from Xiu then maybe I'll go with them. Otherwise I need to source genuine Gas Gas bearings but don't know how to ensure I don't get the dud 2013-15 ones. Thanks, Chris. ps. I couldn't have done the last rebuild without your excellent videos. Thank you.

It appears the 2016 Repsol has the longer (carbon) heat shield as well.

...and you shouldn't need to cut any wiring. The "street' wiring should be able to be removed by disconnecting various connectors. The only thing to watch is that the fan relay is originally mounted behind the headlight. It needs to be retained and re-located to a bracket under the seat (the original wiring is long enough to re-route). Check before riding that the fan comes on a few minutes after starting.

I'm pretty sure the alternator output is 160w. Without lights there should be plenty to spare. ECU and fuel pump should only need about 20w. Not sure about the fan but probably another 30w or so. If you're running the homologated headlight then that could be 35w plus tail light etc.

Seems like there are problems with both types of forks. Unlike the Tech forks, the problem with the Showa forks is not really the seals. It is the teflon coating coming away from the top fork bushes and bits of it getting caught under the seal causing it to leak. Eventually you will have metal to metal contact with the fork tube which won't be good. This is what a faulty bush looks like (and that's not wear and tear):

Unfortunately, the dealer(s) here in Australia claim not to have heard of any problem. They've obviously not heard of the internet either. To each individual they will tell you that you are the only one to have had this problem (implying that it is your fault somehow). Clearly, there is a real problem with the Showa fork bushes from 2015 onwards. I say onwards because, as Oz Thumper says, the replacement bushes are failing as well. Very disappointing.