zippy

Are you saying if you are in 4th gear and give the bike a lot of throttle (gas) the bike will shift on its own into 5th and if in 5th gear it will shift on its own into 4th? There is a known "clunk" and a little hard shift between 4th and 5th and back down from 5th to 4th, that is just a characteristic of the GasGas Pro transmission.

Probably a "certificate" is out of date.

Sorry, best I can do is Australian https://www.thehellteam.com/technical-support/gas-gas-parts-and-service-manuals

You have the TXT model before the Pro model came out. Frame matches the frame in the first photo I posted, look closely at the footpeg area. Also The exhaust header where it enters the midbox is horizontal, the Pro in angled at that point. The radiator on yours is "inside" the frame, the Pro the radiator sides are visible. 250cc vs 280cc, The Pro model has a number in the casting of the cylinder. Shifter side, 25 = 250cc; 28 = 280cc I don't know if the TXT model also has that number in the cylinder casting.

Throw up a photo and the hive mind will be able to tell you. Quick reference - there are other differences but this is quick: TXT model 2002 and before has a longer shift lever 2002 and later Pro model has a shorter shift lever Also frame differences

What is the finger height measurement? If it is too low there will not be enough leverage to disengage the clutch. this is from the 2015 users manual, finger height is 17.5mm +1mm -0mm, other years may have slightly different measurement specs. Credit goes to the Hell Team https://www.thehellteam.com/technical-support/gas-gas-parts-and-service-manuals

You just recently had the top end done. Was the bike running fine before that? definition of fine for this case: continuous running, only shutting off when rider wished to do so. was the engine removed from the frame or only the barrel, head, and piston removed? Start looking at what items were disturbed, disconnected, etc. Any sharp bends in the wiring that could have broken wire inside the insulation.

I think @Andy may have moved on to other endeavors. It has been a long time since I have seen any activity by him. I am not sure how often this site is monitored by him anymore.

and it doesn't take much to shorten the bars to where it is comfortable. I think I cut 1/2 inch off each side. Start small, you can always cut more off, a bit harder to add it back on. Risers won't mess with your ability to learn, being uncomfortable and in pain will mess with your ability to learn. Down side of using risers with low bend bars, it brings the center of the bar up so there is more possibility of hitting your body with the bars on big ups. Bars with a taller bend will give height but keep center of bars out of the way of the body.

OK quick arguing about whether tall or short is an advantage, it doesn't help answer this person's question. @dirtrider86 When you state "older trials" are you referring 10-15 year old machine or even older? - but either way my notes below still apply to both. I used to suffer from low back pain and sore wrists due to riding position. 2 small changes made all the difference so that I could support myself with my legs and not lean on the bars. 1. Bar risers - I didn't go crazy, I think I got the 10mm risers at V-Mar racing. https://vmar.com/barmounts.html#close - Same results could be gained using taller bars. and as @Tr1AL stated be sure to buy Trials bend, this is what they are designed for. 2. Bar width - I cut my bars shorter so that my forearm, wrist and hand were all in line. I will explain, this one takes some visualization to understand. stand on your bike, place your hands as far apart on the bars as possible - notice that your wrists bend outward and your back is bending forward Now bring your hands inward on the bars until your forearms and wrist are in a relative straight line. Your back will also move to a straighter position - you should be able to find a natural feeling position that is still somewhat bent forward. Setting the bar width for my "wingspan" solved the sore back from having a too forward riding position and solved the sore wrists from having them bent at an uncomfortable angle.

@arnoux I use that page many times and direct others to it many times. Thank you for continuing to keep the information available.

Nope, but a short while later I switched to Alpinestars and never looked back. So much happier with the Alpinestars, stiffer sole so my arches don't hurt.

Welcome, and good luck

this should help with that - Credit: The Hell Team in Australia - https://www.thehellteam.com/technical-support/gas-gas-parts-and-service-manuals https://drive.google.com/drive/folders/1DGheDNbhzVPDilvBpBIbRDkkqtXsKuXr

Here are some USA online dealers, not sure how much 2023 items they will have in stock. https://trialssuperstore.com/ https://www.tryalsshop.com/ https://www.trialstoreusa.com/ https://factoryonemotorsports.com/shop-by-manufacturer/ https://lewisportusa.com/ GasGas.com search for USA dealers, Brick and Mortar stores. https://www.gasgas.com/en-us/dealer-search.html

My 2015 GasGas 300 came with a flywheel weight from the previous owner. I noticed immediately that it did not have that "pop" at small throttle inputs, it had to be revved more to get that response. Made the bike feel sluggish to me. I took the flywheel weight off within a couple days. A flywheel weight may provide the result you're looking for.

vindecoderz.com says it is a 2005 https://www.vindecoderz.com/EN/check-lookup/VTRGG280203021230

Tip when lifting a trials bike onto a stand, as tempting and convenient as it is do not grab the muffler to lift the bike. Reach down just a little farther and grab the tire/rim and lift. Will save the muffler from getting wonky and provides better lift to set it on a stand.

First, as Lineaway suggests, verify the magnetic lanyard is on the killswitch on the handlebar I have owned a 2003 GasGas Pro and currently own a 2015, starting technique is the same for both. When cold: Choke on, have the bike on a stand or leaning on a tree, etc., get on the pegs so you are standing on the bike. Bring the kickstart down until you feel resistance, good smooth forceful kick downward. Kickstart will hit the footpeg. that is normal. Should start 1 or 2 kicks, I sometimes give a short blip of throttle AFTER I hear the bike fire. When hot: same thing but no choke After some time and practice you may get to where you can start it flat foot on the ground. Took me some time to get to that point. I don't know if it matters much, but I run 110 race gas at 80:1 mix, with a high compression head

Place bike in 1st gear, set idle so that the bike will putter around with no throttle input without stalling.

There are many that say that style of rim will always leak and is impossible to seal. Best / Easiest fix is to buy a new rim with the 2 piece turnbuckle style spokes. No rim band, no leaks. I did replace a rim band on a 2003 GasGas more than 5 years ago, it sealed up just fine and had no leaks for years. (I did break off a sprocket mounting tab on the hub.... but that's a story for a different day) Use a lot of patience and soapy water when installing the new rim band, I suggest a band with the valve stem integrated in the band. Thoroughly and meticulously clean the rim before installing the new band. Use rounded tire irons (tire spoons), no sharp edges, to stretch the band into place. Use much soapy water and carefully work the band into the groove in the rim. do not use anything sharp or pointed to push the band into place. the band must fit under the lip in the groove. I used the backside of a dental pick, the rounded portion so the point was sticking up away from the band. Also check out this video from Jim Snell, dude has much experience and knowledge. https://www.youtube.com/watch?v=k290LeBasws

L'épaisseur du pack d'embrayage affectera la difficulté ou la facilité de traction de l'embrayage. La hauteur du "doigt" change à mesure que les plaques s'usent et peut modifier la sensation de traction de l'embrayage. Le pack d'embrayage pour 2004 Pro devrait mesurer 9,75 - 9,85 mm. la hauteur du "doigt" doit mesurer 17mm +/- 1mm. Je pense que la hauteur des "doigts" est plus importante. Le ressort rond doit mesurer entre 4,4 et 4,5 mm d'épaisseur. L'image ci-dessous provient de The Hell Team in Australia Divers manuels et livres de pièces https://www.thehellteam.com/technical-support/gas-gas-parts-and-service-manuals 2004 Manuel d'utilisation du GasGas Pro https://drive.google.com/drive/folders/1-4IwVfa6L0JeJxakfxESxU6iZ7GNBelQ Si vous avez besoin d'ajuster l'épaisseur du pack d'embrayage, de nouvelles plaques de fibre peuvent être achetées ou différentes épaisseurs de plaques métalliques peuvent être achetées. Ils sont empilés dans diverses combinaisons pour atteindre l'épaisseur correcte. Exemples en lien ci-dessous. https://www.thehellteam.com/products/engine-parts/clutch-plates/?cn=106&rf=cn À un moment donné, des plaques de pression d'embrayage plus minces (ressorts) pouvaient provenir de fournisseurs de pièces de rechange. Je ne sais pas s'ils sont encore disponibles

I think it would be worthwhile to ensure the passage the actuating rod goes through is clean and clear. To ensure smooth motion.

I am not positive, but I believe they can be removed, and it is a very large torx bit. I don't have one that size, so had no interest in removing them.

I don't know if the Brak-Tec caliper on my GasGas is the same as yours but here goes. I have a 4 piston mono block caliper. I decided to clean the pistons and reassemble I did it one piston at a time. NOTE: I did not remove the large Torx plugs in the caliper. 1. disconnect brake hose from caliper - drain as much brake out of the caliper as you can, some will remain 2. wrap mechanics wire around the 3 pistons you want to stay in the caliper 3. using compressed air "pop" the 4th non-wired piston out 4. At this point I cleaned the piston and reassembled, you would pull the seal out of the caliper with a pick. Lube the new seal (I just use brake fluid), insert new seal. Lube new piston, insert new piston. 5. wrap mechanics wire around the new piston, unwire next piston to be changed. 6. repeat for all 4 pistons.