zippy

yep, get some feeler gauges, and tap that electrode on something solid. I always check the gap of my plugs and adjust as necessary.

YAY!!!!!! Easy fixes are the best fixes

Remove linkage and attach shifter direct to shift shaft, first, Rule out the cheap easy stuff first. Let us know how it goes.

No shame in knowing your limits. You think the top guys spin wrenches on the bikes they ride? There are many websites that offer parts, be advised some parts have been discontinued but many are still available. a few possible options: https://www.rockymountainatvmc.com/ https://www.bikebandit.com/ https://www.hondapartshouse.com/ https://www.partzilla.com/ https://www.hondapartsnation.com/honda-motorcycle-parts

Some information and some opinion. First the opinion, I used to own a tLR200 Reflex. Fun bike, I had the gear shift lever attached direct to the shift shaft. It was mounted vertically, forward for down shift, backward to upshift. This kept it up out of the way and mostly protected, and reduced possible accidental shifts. Question: does the shift lever need moved back to horizontal with every downshift or just when shifting into first? Information, Parts schematics are available on most online parts suppliers for the major Japanese manufacturers. I suspect you have an issue with the shift shaft and return mechanism. Possible 1 "side" of the return spring (#12) is broken off. This will be located under the clutch cover. front of bike in picture would be on the left. Hope you find the issue

The center bolt for holding the clutch basket on is not exactly necessary to have in there, you can leave the bolt and washer out. I am running mine without it. If the basket does move outward it will move a minimal amount before the clutch plunger touches the fingers. which will keep it from moving any farther out. but I am afraid you may need to split the cases. there may be an issue internal of the transmission

No clue what that piece is that fell out when you took the cover off. The Hell Team has much Tech support information. click on "Parts Books" and then click on the year of your bike, and viola!! parts diagrams. I could not find anything that would be under the clutch cover that looked like that piece. https://www.thehellteam.com/technical-support/gas-gas-parts-and-service-manuals.html

I believe you are correct. Here's one. All credit to the Hell Team: https://www.thehellteam.com/technical-support/gas-gas-parts-and-service-manuals.html Number 19

https://www.youtube.com/watch?v=G55FU27Z9bU

Investigate the locked up kickstart first, check the top hat for gear change. Top Hat has a break away bar in it to protect the other bits of the shifting mechanism. (photos below) Starting procedure: have bike on a stand/leaning on something. get on the pegs, set foot on kickstart, slowly lower kickstart until slack is taken up and kickstart engages. at this point kick downwards with smooth authoritative force. DO NOT "stab" at the kickstart this could cause the quadrant and idle gears to chip. if a piece gets lodged between the two gears, it could (most often does) push the two gears apart placing stress on the clutch cover and breaking the clutch cover at the kickstart shaft. credit: Hell Team Website https://www.thehellteam.com/technical-support/gas-gas-parts-and-service-manuals.html Kickstart quadrant gear highlighted Top Hat highlighted; notice the cross bar. If the bar is broken it will be rotated inside the bore of the top hat. the ends of the bar will remain in place in the wall of the top hat. Google searched this photo, source says Trials Central - Added text - Clutch basket has been removed - there should be a hollow allen head bolt in the center of the clutch basket. 4mm I think, not positive

it's a special design feature to remind the rider to keep their knees out................... I don't know if the 2021 and the 2015 have the same exact design for the air box, but I have no issue with it causing any bruising or discomfort.

OP has a 2015. that should have a rear rim with all external spokes. (true tubeless type rim) My 2003 had the rubber seal in the center channel of rim, I replaced it once with a rim band that had the valve stem built in.. Used zero sealants of any kind. Cleaned rim, used a little bit of soapy water when fitting rim band, made sure the rim band fit the channel properly fully under the ridge. Lasted 6 or 7 years until I sold the bike.

My 2003 Pro had the kickstart hit the peg, and my current 2015 Pro kickstart hits the peg. Basically the peg is used as a stop instead of some part of the frame, some bikes have a metal stop on the frame that the kickstart hits (TLR200 Reflex I think had one) It's a design of the GasGas Pro engine. Internally there is "stop" for the kickstart as well. Pro engine has been mostly the same design with upgrades to internal components that retro-fit from 2003 - 2015, I am not sure about retro-compatibility with 2017 -2021 models All credit to The Hell Team: https://www.thehellteam.com/technical-support/gas-gas-parts-and-service-manuals.html My advice: (yeah like anyone listens to me) ride it, enjoy it, crash it, pick it up, repeat. starting procedure, stand on pegs (lean bike against tree, etc; bike on stand; balance on pegs), slowly bring kicker to where it engages, kick firmly and smoothly, DO NOT STAB AT IT - for some owners that has caused problems with breaking the clutch cover. most often starts 1st kick, sometimes 2nd kick. same way for the 2003 I had as well as the current 2015.

that spring has definitely sprung. I am not sure if the shaft on a 14 can be pulled without splitting the cases. My 2003 required splitting the case because of the rollers attached to the shaft being inside the shift drum. I am not sure what the kickstart positioning bush is, do you have a photo?

Did that used to be the spring on the gear selector shaft??? DAMN! The hole in the crankcase is normal, my 2003 pro300 had it as well. some are "better looking" than others, I have not had the cover off my 2015 yet (just got her last summer) but I suspect the hole will be there as well.

Are you are referring to the single allen bolt in the center of the clutch basket? If memory serves me, the head is about half the thickness of a standard allen bolt, but the threads I believe are standard right hand thread. The bolt is also hollow to allow oil to pass through Some use a thread locker of some sort on the bolt. (I don't believe thread locker to be necessary, and I know a couple people that just leave that bolt out)

welcome, hope that's the issue, should be relatively inexpensive

Shift shaft issue. Most likely it is the cross bar in Part No. 10 with the return spring. Cross bar is a sacrificial part for just those instances when crashing on the gear lever. It is accessed under the clutch cover side. https://drive.google.com/drive/folders/0B0Mfile5AhnmN0RMR0lRNGRWRjQ - Page 42 10 - SHIFT SHAFT CENTER LOCATOR AND SPRING MT280238037CT

It's all good, responses passing in the night........

6 IN/LB is just snugged up and just barely a small bit more.

If that model has the standard 6 springs with the small bolt through the center of the spring, If I remember correctly the torque setting is actually quite low. but I don't remember an exact number. I did find for a Sherco, that the torque for the clutch spring screws is 0.7Nm (0.516 FT/LB or 6.2 IN/LB) http://shercousa.com/pdfs/Workshop_Manual.pdf Page 4 of 60. in the PDF I know it is a different brand, but the clutch design may be similar enough that the torque is similar as well.

Yep, TXT series for GasGas. Good luck hope ya get it back to running good again

If it has a history of running good until one day just is not running well, I would suspect a blocked jet. Take the carb apart, clean it. throw it back together and see if it's fixed. I believe so, but still a GasGas and basic running principles are the same. (Maybe we can convince @mastermatt to buy a GasGas trials bike too)

with the idler gear broken, be sure to check over the "Bart" gear on the kickstart shaft for damage as well.

I believe it was a 2015. Just be sure to use your spacers that are original to your bike on the new wheel.