konrad

The nice thing about lemur's suggested gauge is that I expect it would be very tolerant of over-pressure.

https://www.electricmotiontech.com/home/em-epure-race/regen-experiments#h.7lz2uhjj7x3c

https://www.ossa-efi.com/home/electrics/fuel-injector/fuel-injection-pressure Suggest you download all the factory documentation here: https://www.ossa-efi.com/home/factory-documentation Try searching for the barb by part number.

My experience has been that digital pressure gauges that read to 100 psi or so are very inaccurate at trials pressures. Maybe you can find one that claims to be accurate, but I doubt it will be as cost effective as buying another Apico. On the plus side, you probably won't make the same mistake again.

I have a little experience with this. As you know, replacing the guides is not typically a DIY job. After installation, the ID needs to be reamed to size and the seats re-cut. The US company Kibblewhite manufactures aftermarket valve guides (and other head components as well). See: https://www.kpmi.us/ The potential problem I see with gas-flowing the ports is that the technique is generally used to improve WOT flow. Unless the person doing the work has experience specifically with trials, the results may actually make the performance worse.

Search "jwpf extension cable." AliExpress would seem the most likely source for a single cable. Are you sure the TKO function can be switched in real-time? Maybe EM put the switch where it is because the controller only senses its state at boot-up or when the mode is changed? I don't know. But yeah, it does seem like a horrible place for the switch itself.

You are absolutely right, it was the pump test I used to drain the tank. Just ran the injector test on equipment in my lab. That test generates five approximately 100-microsecond pulses, 1 second apart. So yeah, that is not going to squirt any fuel! I think maybe they did it that way so it would not flood the engine? It's more of a test for the design engineer than the repair technician. Thanks for making me take a look at it.

Something weird going on there. I have used the injector pump test to drain the fuel tank: https://www.ossa-efi.com/home/chassis/fuel-pump#h.aueu7tpf4lup

EVERYTHING in a carb needs fettling.

The specs for a 2003 290 with PHBL26BS carb are: fuel screw 3.5 turns out from lightly seated. Clip 3rd groove from top. The idle screw should allow the slide to be "a little bit open." Very roughly, you want to be able to get a 2 - 3mm wire to pass under the slide. But this is all just a starting point. The local fuel, premix ratio, atmospheric condition, cleanliness of air filter, and rider preference all play a part. BTW the standard pilot jet is a 33. This jet must be perfectly clean! (And it's the thing that gives most people trouble.)

I just discovered that YouTube will auto-translate closed-caption transcription into the language of your choice by clicking on the gear icon in the toolbar. So what did I learn from reading the captions...? For one thing, the FACTOR-e project had been in development for over 3 year at the time this video was made. But more importantly, I learned that Marc Colomer had to be disingenuous in interviews regarding the ePure saying, "...there is no need to change gears...." Read it for yourself, starting at about 3:12.

Is that a Beta Explorer? How far can you go on a charge?

For your testing: ECU pin 4 is the high side (+12V) for the injector. The low side (switched ground) of the injector is ECU pin 18. There is a small pilot current (89 uA) running through the injector when it is shut. This allows the ECU to verify the injector is electrically okay. On the dead ECU I reverse-engineered, I found the IC that deals with this pilot current was fried. I hope that is not the case with your bike! One possible troubleshooting technique would be to power the injector directly from a 12V source instead of via ECU pin 4. ECU pin 4 wire color is pink. ECU pin 18 wire color is white with a green stripe.

You have fuel pressure and can hear the injector clicking. Doesn't that mean the injector is clogged? I would not expect to learn much by putting a voltmeter across the injector. The duty cycle is quite short. You'd need to use an oscilloscope.

Seems like that should solve the problem. I did not suggest that as a solution because it seems most vintage riders would prefer to clutch as little as possible. When I transitioned from a 2T to a 4T, I basically pulled in the clutch whenever beginning to decelerate. Then I'd slip the clutch until I got the "correct" amount of engine braking for the situation. Now with an electric trials bike, it's exactly the opposite problem. So I have engineered-in a small amount of automatic regeneration on closed throttle.

Now you've got me curious! What is it?

Altering the chassis geometry can help accomplish your goal. Lowering the front and/or raising the rear will make the bike turn tighter with both wheels on the ground. This will help prevent the front from "pushing" too. But, it's all a compromise and the radical changes will negatively impact other aspects of the bike's operation -- like how easily it wheelies and the amount of ground clearance it has.

I think taller gearing would be better than shorter gearing. Prove this to yourself by putting the bike on a stand in 1st gear. Attempt to turn the engine over by turning the rear wheel. Pretty difficult, right? Now, try the same thing in top gear. MUCH easier. Another thing would be to set the idle speed higher.

I don't know anything about the Oset 20 Lite, but this source https://www.ultimatespecs.com/motorcycles-specs/oset/oset-200-lite-2017 says it has a maximum power output of 0.9 kW. Your lithium-ion battery is rated 42V and 160A, which would permit a maximum power output of 6.7kW! Even when the battery is depleted to 36V, it's capable of providing 5.7 kW. Electric vehicles are a system comprising motor, battery, and controller all designed to work together. Your controller is protecting the system from that very powerful battery by temporarily shutting off. Basically, your Li-Ion battery has "upset the balance of power."

Parts book and service manual I found online are for slightly earlier models. It's possible your 2024 is different.

There are many ways to test a capacitor, but if you don't already know how, you probably don't have the proper instruments. In that case, substitution of a know-good part is the best method. eBay is probably the easiest (not necessary best) place to buy capacitors. A prior post said, 4700uF @ 25VDC. But I have no idea if that is correct. Whatever the value is, it should be rated for 105 degrees C. Look for a capacitor specified as having "low ESR", or better yet one that specifically says it's capable of withstanding high ripple current. Some capacitors made in China are okay, but unless you have experience with a particular manufacturer/vendor, I would suggest buying a capacitor made in Japan. If you buy Chinese, buy several to have as spares.

The service manual I linked shows different wiring diagrams for the 2ED (street) and 4ED (competition) version. The only handlebar controls on the competition version are the map switch and tether kill switch. That's all you need to make the bike run.

Honda makes the best service manuals in the world! This is for a 2020 model 301: https://www.montesa.com/wp-content/uploads/2020/03/OSM-301RR-2020-EN-Web_V04.pdf Look for "Cable & Harness Routing" .PDF page 36 (manual page 2-13) shows the rear harness. Seems easy to remove. I did not see anything specifically about the 2ED front harness, but it may there too.

+1 When I would take newbies trials riding, they always asked about boots. I would recommend any boots (hiking boots, combat boots, even road racing boots) before MX boots. One local motorcycle accessory shop found that although it was not worth stocking Gaerne trials boots for trials riders (not enough of them), it was for adventure riders. I like my Gaernes for building sections. I prefer the stiffer Alpinestars Tech Ts for actual riding. It's really important to try on any boot you are considering, as there is no size consistency among manufacturers. And I've even found a "pair" of boots that felt like totally different sizes.

Translation: In case it helps anyone. My Montesa 301 2024, after installing the open exhaust, runs badly, it smells a lot of gasoline and the idle is unstable and ends up stopping. This bike requires the P71 race control unit. The P61 does not work without a lambda probe and catalytic converter.