totty79

I'm pretty sure I've read posts on here about this from someone a few years ago. Sorry I don't remember the outcome but it's worth trying a search. I haven't noticed any bubbling with my Evo.

Bike weight is a killer when you're learning, not because of the difficulty riding it, more the difficulty retrieving it from where ever you've got stuck. When I went from a Gas Gas 321 to an Evo 250 the main improvement in my riding came from being less knackered and from being more willing to have a go knowing that retrieving the bike wouldn't be that bad, and the 321 wasn't even that heavy it's basically only one generation old. It took me about 6 years of riding before I reached the level where many of the things that were still challenging were also a bit higher risk than what I was up for and a less capable classic bike to make the safe stuff harder seemed a good idea. Unfortunately I've regressed back to spending half the day dragging the bike about again so I'm pleased I stuck with the Evo.

Beta clutch can be made progressive (plates, spring preload, clearance and oil are all factors) but although I ride a Beta I prefer the gas gas clutch. Might be worth sticking with the rev3 if the bits that matter are in good condition, same motor as the Evo, and a 3 or 4 year old bike could easily need a couple of hundred quid worth of parts to refresh it if maintenance been neglected The other 250s I've tried were livelier than the Beta. Most 125s are compared to 250s lively rev happy things but with less power, and they feel lighter. I think they're fun to ride but not everyone gets on with them. Some 300s can plod along nicely on the torque at low revs, they aren't all beasts, but there is a more risk of them catching you out.

Nope not my bike, nothing to do with me at all. I said that it may have been done unnecessarily, I never said it should be needed so what's your point. Considering a bike abused and advising against it because it's had an engine rebuild makes no sense at all, it could be in mint condition for all we know. We have no information to go on. The advice the OP needs is on how to inspect a used trials bike, basically what is the state of all of the serviceable parts, how to gauge how much use it's had and checking receipts to see what the rebuild entailed and who did it. I'd even say there's nothing wrong with a well used bike if well maintained and priced accordingly. Hughie, listen to trapezeartist and lineaway they've given some good advice.

I don't think you can read anything into the engine rebuild, the fact that it was done implies nothing of use, any concern should be limited to was it done right and what condition is the rest of the bike in. While rare in modern trials it's very common with 2 strokes to change pistons and crank bearings as preventative maintenance, just look on the forums for any road going 2 stroke and you'll see people being advised to rebuild any newly purchased bike before riding it, I've seen it on tzr and rd sites. People come on here every now and then from MX backgrounds asking how often they should do a rebuild.

Any bike ridden in water and mud will need regular maintenance mainly to brakes and bearings, it's unavoidable. I also don't buy into carbs being high maintenance, I've needed to clean them once or twice at most in the last 10 years. Keep the fuel clean and the air filter properly oiled and they don't cause problems.

Knees need to be thought of as part of the suspension absorbing movement or loading the tyre as required so mostly bent.

125s tend to be in a higher state of tune than 250s, the performance gap is much smaller than implied by the cc. 125s can be a lot of fun and are more than adequate for most riders.

Seats just tap out from behind with a long drift. Try to keep it square as you do it. Lower bearing can be a pain to get off the stem, it's not always needed but it's common to cut the old one. Leave the new bearing seats and stem in the freezer overnight to help with reassembly. Also check dimensions of bearings, seals and spacers against the old ones before reassembly, aftermarket kits don't always get it right.

If you want lively go for a GG300 that has not had a low comp head fitted. They're too much for use in trails sections for many riders so may be the closest to what you're looking for, and for trials they're nice with a low comp head so you might see a few with one fitted. The 250 is more lively than a Beta but not by that much. I wouldn't write off the advice that it's pointless buying a trials bike for anything other than the tight and technical as snobbery though, there's a lot of truth in it.

300 GG is lively for a trials bike, but it'll still feel gutless compared to 350-450 MX bikes and it's not just the motor the suspension, brakes, cooling, tyres etc aren't built for speed.

Yes, but I'm not sure of the point of the question? I only pointed out that ethanol is not vegetable oil, just a simple correction. Nor have I tried to dissuade you from removing ethinol. I even listed it as one of the options and stated that the reduction in octane would be ok for most bikes.

Ethanol isn't a vegetable based oil it's a distillate of fermented vegetable matter. Removing ethanol lowers the octane rating of the fuel, which would be ok in many but not all bikes. Mixing is a consideration but it doesn't appear to be a problem, the can of e10 that I mixed with rock oil strawberry did not separate. (for now I'm hedging my bets with e5 but when the panic buying happened for a few days I could only get e10)

I wonder how many modern bikes actually need rather than just specify higher than 95 octane, there's quite a range of compression ratios starting as low as 8.9:1, there are other factors but shouldn't 95 octane be ok for at least 11:1

We go through this with every fuel grade change, all the same things were said when we went unleaded. Parts have always failed and that failure has always been attributed to the latest change. Rubber and plastic parts degrade, chemicals further degrade them, and if they aren't spec'd right the process can happen pretty quickly. If a part isn't suitable for use with ethanol then increasing the amount of ethanol should speed up the process, but many of us will also remember loads of hoses, seals, taps etc. failing on 4Star so failures are not new they've always been consumable parts. The choices really are to use e10 or e5 with no knowledge of the odds of parts failing early as all we have is anecdotes, to remove the ethanol or buy Aspen, or to fit compatible parts. It's not a great choice, but it is what it is. Also e5 and e10 is just the maximum allowed content it doesn't tell you exactly what you're getting, if you do the water based removal process accurately enough then you should be able to measure it.

cc is a factor in engine character and performance but it's just one factor it's not like every 200 or 300 is the same, there's a massive difference between brands and also differences between years and sometimes even between intended markets. "Instant pop" is as much carb/ignition timing/reeds/flywheel/gearing as it is cc. It's also the characteristic that doesn't work with mud.

Check the push rod clearance and bearing condition as well as clutch fluid condition and bleeding. If the release mechanism isn't in good condition you'll get drag regardless of the oil used. I'd also 2nd nano trans, 300v is also fine, ATF is good for avoiding drag but will make the clutch less progressive.

Given the age of the bike who knows what state of tune it's in, it could have a high comp head, it could even have had some porting changed. While those things would be worth checking I think it's more likely though that as you've pointed out it's just a large step away from what you're used to. The two posts above are also spot on. Read the sticky thread regarding the clutch, a less snappy and more progressive clutch will make a massive difference and allow you to use it to smooth out the power delivery. You need 300V or ntrans oil and a reduced spring preload either by removing two (if you don't use 5th gear where it's likely to slip) or by using washers as spacers, you also need to have the pushrod correctly shimmed - manual says 0.2 to 0.8mm but as close to 0.2mm without going under it is best. It may take two oil changes to get the full benefit.

While there more risk to the back and chest, I find shoulders and elbows often take more of the impact so I wear a top that protects all of these areas. The one I wear most is from Bliss Protection but it's around £160, I've got an older O'Neal one but it's back protection isn't as substantial (like the chest on the Jitsie), I don't really notice either when riding. The current O'Neal version looks better than the one I have but most companies that do cycling or motorbike protective kit do a full top. Hard to tell what chest protection the Comas one offers, I can only make out the back protector in the pics Jitsie looks like it covers a good area and also the kidneys - but it also looks like it's just embedded hard foam, only the back protector seems to be an insert.

For bikes that have a rear suspension linkage in the usual place I don't think there's much difference in the time required to strip, clean/replace, lube and assemble. Each one tends to get easier after a few goes. Amount of play and the frequency of maintenance are much harder questions. With new seals, bushes, bearings and marine grease on my Beta Evo it was still full of clean grease with no play 18 months later after riding roughly every other weekend. It goes downhill after that though when you just clean and repack with old parts to extend the life a bit it and it needs doing more frequently as everything starts to wear, once there's enough play to feel a tap/clunk when riding or any notchiness when disassembled it's time for new parts again.

Some 300s are vastly different to a 250 but in my opinion the Beta isn't, I'm not a great rider and I can easily ride them back to back without having to over think it. As standard they're fairly tame, nice smooth and torquey low down, a bit livelier than a 250 if you're heavy handed but they aren't aggressive. If you're a chug along on low down torque kind of rider the 300 may be preferable, if you're a bit rev happy then you might actually get on better with a 125. Unless you're happy to change it you may need to ask more about the head. It's the head insert that matters not the cover, you can see it around the spark plug, they may do a blue insert but I only recall seeing silver, red and gold. I think the standard insert or the low comp would be best.

4t noise trends to travel further even if the bike seems quieter to the rider. 300 GG can be a bit of a beast, but they can be tamed with a low comp head and retarded timing and in this state of tune they are very user friendly.

It could be a seal problem at either end, or contaminated pads, but I'd suggest ridding it before doing anything else. They tend to be weak after any work on them and they improve with a little use, the heat it up and chuck water trick on it can also make a big improvement. Pads need to be nearly new, the minimum thickness is less than half worn on many pads. If it doesn't improve you'll need to pop the pistons out a strip the master cylinder and rebuild/replace as required.

The threads don't need to engage equally, you can put it a half turn onto the tank then add the tap (or the other way around), it just makes it less fiddly and reduces the chance of cross threading.

You've most likely got tension on the throttle cable, one end not seated right or cable not routed right. Easily done. Best to check that the slide taps on the Idle screw before you start a bike. Just apply a small amount of throttle and let go, and listen for the familiar tap sound.