konrad

I find this counterintuitive, but if you blip the throttle, the clutch will release better. I've only ever noticed this on trials bikes. If anyone has an explanation or theory, I'd love to hear it. I've also found that dimpling the clutch steel plates has a very positive effect on clutch release. But this is a well-know trick, that I probably first saw on circa 1970s Suzuki OE plates.

May I ask where you got that design? Was it done by an A.I. chatbot?

Yes, but I would advise caution. Pin 22 is driven by a component (Rohm SP8K22 dual N-channel MOSFET) known to have failed on at least 3 Explorers. This renders the ECU useless. I don't know of any trials model to which this has happened. I assume there is something about the Explorer wiring harness/easy start that's causing the failure, but I don't have one to investigate.

From my notes... There is a symbol on the initial 2011 wiring diagram called "Testigo Averia". That translates as “Fault Witness”. I called it the CEL (Check Engine Light) in my notebook. Another name is the MIL (Malfunction Indicator Lamp). Looks like OSSA made it part of an instrument panel in the 2014 wiring diagram. Reverse engineered it a bit. It sources 5 volts at only 5 mA, so not too useful to drive a lamp. Even an LED is pretty dim. But, you could easily read it with a voltmeter. If your bike does not start, see if ECU pin 22 is at 5 volts (with the bike powered by a battery). This would indicate the ECU thinks there is a problem, versus the bike just being recalcitrant. Wiring diagrams are here: https://www.ossa-efi.com/home/electrics/wiring-diagrams

The write-ups are quite technical, but maybe some here will be interested. This link is the actual retrofit process: https://www.electricmotiontech.com/home/em-5-7/sx-controller-retrofit This link describes some preliminary work to familiarize myself with the SX controller: https://www.electricmotiontech.com/home/em-5-7/sx-controller-experiments

The trials model definitely had superior suspension to the Explorer. But I think going forward, the Explorer will be a very desirable bike. I expect some trials models will get sacrificed to keep Explorers running. I'd suggest buying a ratty trials model to use as a donor.

Here's my analysis of that dyno comparison: https://www.electricmotiontech.com/home/what-makes-a-good-trials-motor/zero-loss-gearbox-anlaysis

Beta has a 6-speed box. I'll let you do the calculations.

I think you want something with a 6-speed. Here are overall ratios for two "obsolete" bikes. OSSA TRi 36.93, 29.99, 24.78, 20.73, 14.2, 8.45 Aprilia Climber 37.81, 29.65, 21.5, 15.45, 12.18, 8.45 Plus, one current bike (but it uses GG's 4/6 system and shifting will be more clunky than a true 6-speed). GagGas Pro (all) 31.77, 27.27, 23.19, 19.91, 11.93, 8.7 Here's the Montesa 4RT for reference 36.36, 30.97, 25.97, 16.53, 10.58

Fully extended. The air trapped inside acts as a spring. Although the pressure would probably eventually equalize itself either way. Longer travel forks often have bleed-screws to release excess air pressure when the forks are fully extended.

This is a topic near and dear to me. I keep spreadsheets with gear ratios for a variety of bikes. Modern trials bikes will all have the same problem, a wide gap between the "section" ratios and the "loop" ratios. The most even spacing I've measured among trials bikes was my old TXT321. Never had that gearbox apart, but counted motor revs per wheel rev as: 39.25, 33.75, 26.50, 20.75, 13.25, 9.00. Typically, a 6-speed box will offer a slight improvement over your Sherco's 5-speed. FWIW, I've discovered that single-speed electric trials bikes work really well as a technical trail bike.

Fill and drain bolts are both M12 x 1.5

Clearly, someone before you has had it apart. Is the top end getting sufficient oil? IIRC, there is an oil pressure check bolt in the head. There's no oil filter but, there is an oil screen that can be cleaned if you remove the clutch cover.

TT-R125 manuals are available online. Valve clearance (cold) IN: 0.08 ~ 0.12 mm (0.0031 ~ 0.0047 in) EX: 0.10 ~ 0.14 mm (0.0039 ~ 0.0055 in) Check the cam chain tensioner too.

Regarding ticking, have you checked the valve clearance? Regarding low-rpm hesitation...

I'd strongly suggest borrowing a bike to see if you even enjoy the sport. You could easily spend far more time tinkering than riding. Which is fine if that's what you want, just understand what you are getting yourself into. You'll need well-developed mechanical skills from some other endeavor.

It's just an old Aprilia model name. Here's a pic of one: https://www.james-pratt.com/2023/01/working-on-my-very-rare-aprilia-280-climber-trials-motorcycle/

I have always assumed there was a sponsorship deal. A friend calls that oil "Elf Tears".

From my maintenance log, both oils every 15 - 20 hours. Filter every other oil change. I'd say it depends a lot on conditions of use. Sending a drain oil sample for analysis can be enlightening. Don't wait 40 hours to check the level.

If you weld it, the bore will have to be re-machined. That's a reasonable place for JB Weld, but after the bearing is installed. Don't press the bearing in, heat the case and cool the bearing so it is a clearance fit and drops in. I've written a bit about bearing fits and CTE which may be helpful: https://www.ossa-efi.com/home/engine/gearbox/locker-shaft#h.3t5em1loxmz9 EDIT: looking at the photo again, Beta thinned the casting section where it is cracked. This would be stupid to do if not necessary. So, another part must be in close proximity. This complicates things.

Are you using a Dellorto? If so, they have replaceable starter jets. When I did not want to wait for jets to arrive for my my old TXT321, I just enlarged its original #60 starter jet hole from 0.023” to 0.028” (making it approximately a #70). Much easier to start! Figured I had nothing to lose, as I could just solder up the hole and re-drill to original size if it made things worse. The jet number is the approximate diameter in millimeters, so a #60 would be about 0.60mm in diameter. When I drill a jet, I obliterate the original markings.

That tone is being produced by the motor. It's indicating an error occurred while the controller was performing its "pre-flight" diagnostics (which take about 2 seconds to complete). One example of such an error would be the throttle being open during the diagnostic tests.

I have never seen a video uploaded directly to Trials Central. Pretty sure you must use an intermediary server (like YouTube) and then post a link. Try unplugging the connector for the Regen button. It will be labeled something like "FRB" for fixed regen braking.

Do you have the variable regen lever option? If so, unplug it as a test.

Not sure what you mean by a "low pulse tone from the battery." There is a large contactor inside the battery that makes an audible clunk every time the battery is switched ON or OFF.