mcman56

What color spark plug are people getting on their Beta 4t? I have a 2016 300 with standard muffler. With 115 main, 20 pilot, mid needed (white plastic space below) and idle mixture 1 turn out, plug is powdery looking black. Riding at sea level at 60 to 90 degrees F, it runs OK but it seems the plug is way too dark yet jetting is lean compared to what I see others are running.

I agree with B40T. start bike, make sure you have some open space in front, give the bike a little roll forward with your foot and ride 10 or 20 feet with clutch in until it clears. A little blip of the throttle should do the trick. Some modern bike clutches stick too.

Does anyone know the fork oil volume or height for a 2001 Rev 3? Is it the same as a 2008? Is there a place to get a 2001 operator manual?

I stretched the caliper and installed a KX65 brake disc (180 mm vs 160 mm) and got a more powerful brake. Still, initial feel was not as good as I wanted. Next I noticed that if I put my heel on the peg it felt pretty good when braking. This probably only applies to us wee people with small feet (size 9). I have been wearing boots with heels and noticed it felt better with the heel shoved up tight against the rear of the foot peg. Comparing a Rev 3 to the Evo, front of foot peg to brake tip distance is about the same. However, the Evo has wider pegs so with heel, it forces your foot about 1/2" further back. I took BM1200s advice and bought the Jitsie pedal. It does come farther back so I'm hoping that will do the trick.

I looked at 2 bikes yesterday. 2016 Beta master cylinder has Beta cast in. A 2019 Beta Factory has what I think is a Brachtek symbol cast in and boasts of better brakes. Calipers looks the same except that the factory caliper has some dot matrix pattern on the back with numbers. 2019 felt better. Still, what can really be different? They look to be the same size. A bigger piston would move more fluid but have less psi (pounds per square inch). A smaller piston would move less fluid so would require more travel but would have more psi so maybe that would be the direction.

The REV3 rear disc is 5 mm bigger in diameter. I tried comparing the REV3 pedal to the evo pedal. The REV3 does look longer but there are so many curves it i shard to put a number on it. I believe other brands like Gas Gas actually have smaller discs

Are there any new learnings to improve the evo rear brake? I had a 14 Factory with weak rear brake and tried everything, all kinds of pads, new disc, replace master cylinder and caliper with latest (2017 or 18?) Still it remained much the same. It did not feel spongy, just weak. If you stomp on it, it will stop but it is not easy to finesse in technical situations. Now I have a 2016 evo that is the same. Others have had a similar experience. My rev3 rear brake was vastly superior. I have ridden 2019 and maybe 2018 models that have quite nice rear brake feel but when I look at all of the hardware, it looks the same. ?????

Standard factory recommendations seem to be 1 to 1.5mm

I find pulling with vacuum from the bleeder nipple to be the most effective. When changing fluid you can just keep it always full so there is no air to bleed. I also use the push with syringe method and the pump and release method. Sometimes I think the different methods help get bubbles out of different places when it does not go well. Still, bleeding hydraulics on a trials bike, particularly starting with a dry rear caliper, can be a very frustrating job. In addition to methods and techniques, I often feel that there is some sort of higher power that requires a certain level of emotional suffering from the mechanic before allowing those last few bubbles to exit.

Starts and runs fine until riding to sections then smokes excessively If the exhaust is full of oil, it may catch fire and smoke excessively when riding to sections. It will also run funny and have a weird smell, sort of like a rancid barbecue. You could be burning off the oil that built up from the bad seals. There are some posts on here about cleaning out the exhaust. Another way is just to run it hard and keep a lot of heat in the exhaust until it burns out. This could be a long ride at the speed it starts smoking on the way to sections or a nice long hill climb. Repeat until it stops smoking.

What drugs could help trials riding?

Keihin PWK does not come in 26mm

Personally, I have found the Keihin carb particularly insensitive when trying to adjust by the "fastest idle" method. In fact, one day I was riding with a rider on a new 250 Evo and when he went to adjust the idle mixture screw found that it had fallen out. The bike still ran OK. I try and use the "adjust and try" method. Not that I would recommend it but a 26 mm OKO would be a simple swap as it is the same size and uses the same cable.

I'm not sure if this helps but have you looked at other Beta models? The 08 Rev3 200 fork has a different part number than the 250. I have long suspected that it is a softer spring. Could the new 125s have softer springs? Beta may know. You could compare the rear shock springs to a 125 to see if they are different. A suspension shop, like racetech, may also be able to provide a spring by looking at the originals even if they can not look it up by make and model.

Has anyone come up with a chain guard mod to keep the chain from sawing through boots?

Did you bleed out and refill the cartridge per the owners manual? It is what lineaway is referring to. It is not that hard to forget if you have not done it lately.

I see a manual and parts list here. There should be an alternating number of steel and fiber plates. Interesting question on weather the piston could pop out of the slave cylinder if not retained by the clutch. https://www.overlandtrail.biz/Montesa Parts Books.htm

Where is your focal point when doing a zap? I noticed that I'm getting over a good sized log off the ground fairly easily so am likely getting some lift there. There is a little hill a couple of feet behind the log and I am focusing on getting the front wheel on top of the hill rather than stuffing it into the hill. The focus is the angle of the bike and destination. The undercut areas I have been trying to zap don't really have anything behind them to focus on. I'm just focused on the edge of the step and using my legs. Mostly, I end up hitting the back of the bash plate (which is right under my legs) on the edge I'm concerned that I'm doing what someone recently told me was an MX saying, "look down, fall down.....instead of.....look forward, go forward".

You need to pull the flywheel so need the appropriate puller. Then it is just a couple of screws to remove the plate...pretty easy. Instructions are in the link. https://shop.betausa.com/p/evo-4t-oil-pump-upgrade-kit-09?pp=12

I bought a 2016 300 4t last year and noticed that American Beta sold an oil pump upgrade kit to decrease engine braking. I believe it was the same as the 2018 models so I bought one. I got used to the engine braking before installing so this past year it just sat in a cabinet. Recently, I have been going back and forth the between the 4T and a 2T and the engine braking was the most challenging part of transition so I finally installed the upgrade. It is just a slightly wider (3/16" maybe) pump module. It makes a significant difference. I actually forgot about the install for about 1/2 of the first ride back on the 4T and did not notice braking so it did the trick.

"starter motor and then switched to generate power" 1970 Yamaha AT1 125 had that

I was concerned that it may not be strong enough for 120 NM but it would explain why it has the locking bolt. Thanks

How do you hold the flywheel when tightening the retaining nut on a Beta 4T? (post 2014 2Ts may be the same) There are no threads to interface with like the older 2Ts. I bought a Tusk tool for this purpose but it is too small to fit the flywheel. I have a rubber strap wrench but it can not get a good bite.

Except for turning, I don't use the clutch much. Do you have any suggestions on developing that skill? Do you try to rev and dump or hold high rpms and feed?

I checked the reeds and I actually did not have the boyesens installed. I installed them and fully advanced the timing. There is a noticeable improvement. I have a 26mm OKO and wonder if it could improve response over the Keihin. It is interesting what this site says about Keihins on 125s. https://trialendurodirect.com/product/gas-gas-pro-performance-kits-ppk5/ The Keihin carburetors make a BIG difference to all GG Pro models. The standard 26mm Dellorto carbs are great for production because they carburate perfectly and rarely change whatever the conditions. The Keihin carbs are 28mm so that’s 2mm bigger than the dellorto which increases top end power, this is why all the top riders use them. Also because of the 2mm bigger bore they make the bottom end power very smooth and clean. The carburation is a little more tricky to set up and can vary in different conditions but the Keihin carb we supply should be spot on for all 250/280 and 300 Pro models. Only maybe a slide change is necessary. Fitting the Keihin carb to a 125cc will improve the top end power alot but you lose quite alot of bottom end which is maybe not a good thing for a 125. It depends on ability of rider and conditions used.