coxy

Hi Currently rebuilding a front brake calliper on a 2010 Gas Gas pro which I was having trouble with the front brake binding and getting hot causing the front wheel to lock. Dismantled the calliper and removed the old pistons and seals to put fresh ones in. I have thoroughly cleaned the seal grooves and calliper ready to put them in. My question is does anybody have any tips for installing the new front pistons and seals? obviously a bit of brake fluid on the piston will aid installation but any other tips? Can the pistons be put in the freezer to make them smaller to ease installation? Cheers

Im presuming by your comments you've ground down the open end of the 13mm spanner you are using? Turn it round or use a ring spanner instead and grind down the ring end to fit. Make sure you use the star ring spanner with lots of small contacts instead of the ring spanner with only 6 sides as you can get the spanner on in more places. Thats what i did when i refreshed the top end on my gasser and it worked a treat. The ring end of the spanner will be quite thin but will have enough strength to undo the nut. Hope you understand what i mean and hope it helps.

Thanks for the replies I did think that having it replated seemed abit excessive to say it's only a 2010 bike which ive owned from new and its not been thrashed or anything. The bike sounded sweet as a nut before I took the head off so can't see any reason why I would need to do anymore apart from put new rings in it

Hi Ive been having trouble recently with my cylinder head o rings and thought whilst I had the head off id put a new set of rings and little end bearing in the bike to freshen it up abit. Its a 2010 gasgas pro 300 racing thats probably got around 800hrs on it minimum.(4hrs per weekend 52 weekends a year x4) and was wondering would I need to have the piston replaced and barrel replated or not? The piston looks pretty good, only has a slight amount of black around one part of the piston and the barrel has no dark or grey patches or any lips or markings so would you put a new piston and get the barrel replated or not?

My dad has a fiesta which does the same as your buggy. Its due to condensation mixing with the oil around the oil filler reservoir. With the bike I think I've found what is causing the grey sludge. The small o ring sealing the two inserts for the cylinder head is leaking which seems to be causing the coolant to oxidise and create the grey sludge stuff. Just need to sort out the poor running now

Hi Ive got a 2010 gasgas 300 racing that isn't running very well and believe it could be a cylinder head o ring issue. when starting the bike after been stood a week the bike runs very poorly for the first minute or so and the bike gets very hot until it clears itself and then will run ok and temperature will be fine after that On low or high revs but if a short snap of throttle is required then it splutters and won't rev crisply. When I looked into it the plug is black but when checking the coolant there's a grey coloured sludge in the filler cap (see photo) but no visible loss of coolant. Could this be a cylinder head o ring problem and coolant is getting into the cylinder or oil/fuel mixture into the coolant? Ive altered the mixture screw both leaner and richer and it makes no difference to the engine when a small blip of throttle is needed.

Try taking the caliper off, removing the pads and give all around the pistons and inside where the pads sit a really good clean. I have had the same issue several times and found that cleaning the inside sorts it out. Think it is because mud goes hard and sets around the pistons/seals and then when the bike is used again the hard mud won't let the piston return causing the brake pads to bind causing the extreme heat. I now carry a 5 litre bottle of water in the van so if I happens I pour some water over the disc etc and it usually sorts it out so I can finish the trial and get home and then give it all a real good clean

Coolant colour isnt important as you find that it changes with different companies. What is important is that you get a coolant which is safe to use with aluminium. I use putoline coolant in my 300 racing with no problems and its a green colour

Im currently running my ec300 at 2% mix which is 100ml of oil to 5litres of fuel. Ktm manual states that your bike should be running at 60:1 which is around 85ml of oil to 5 litres of fuel. Anywhere between 85 and 100ml of oil would be sufficient with a good quality synthetic oil really

Thanks for your help. I know last time i had one sent off the guy who did it returned it to the settings that gasgas used. I just wanted to get the spring length and damping settings which gasgas set them to as a base so i can then make my own adjustments and also see if he had set it back to factory

Hi i have a 2010 gasser 300 racing model with the ohlins rear shock. Could anyone tell me what the standard settings are for spring length and for damping. I presume that when its been rebuilt it was put back to standard settings but just when to check Thanks Coxy

Is it the standard sachs shock that you have or do you have an ohlins shock? The ohlins can definitely be rebuilt i had mine on my last bike rebuilt twice due to it dumping all its damping oil which sounds similar to whats happened to you. Im pretty sure the sachs shock can also be rebuilt but not entirely sure who by though. If you search for shock rebuilders or specialist near your area and give them a call you might be able to get some help or find someone who will rebuild it for you

I had exactly the same problem with my back brake about a month ago. It was the seal thats had gone in the master cylinder that needed replacing. About

From what i remember it also damaged the casing gasket. Best thing i would say to do is to check it or put a new one on for the small price which a gasket costs and then cut the rubber down so it doesnt happen again.

Ive not got a sherco but know a few people that have had the 2012 model who have had that problem. The problem was that when riding the bike and landing on the sump it would push force up through the rubber which would in turn push the clutch casing up causing the casing to move and leak oil out the bottom. The solution was to cut the rubber on the clutch casing side so that it didnt sit under the clutch casing itself just under the engine. Hope that helps.