Hello again. I know the choke on a cold engine causes higher rpm but mine revs so high when the choke is on I worry its ruining the engine. When the choke is then switched off the revs are fine. It certainly isn't healthy for a cold engine to rev that high. Carb is a dellorto. All the inlet rubbers are new so i don't think its an air leak. Could the choke itself be worn causing this high revving. Carb has been stripped-down and rebuilt. Any ideas ?
I found it a struggle many years back when I had a Rev 3 250 to screw and unscrew the right hand exhaust bolt. But on the 125 it's even tighter. My long reach t handle allen bars cant do the job. Normal allen keys cant get near it. Ive resorted to fiitting a hexagon headed nut and using a reverse spanner to tighten it up but it takes ages as you only have about 30 degrees rotation of the spanner. Would a ball headed allen key fit an allen bolt on the right exhaust bolt ?
One product I have used consistantly over the years is J-B Weld (see jbweld.com). It is a two part epoxy and once hardened you can drill, grind or machine it. Works great on engine cases.
Just used the JB Weld.Amazing stuff. Took a day to go off properly as it has been so cold. . Looks good after sanding. many thanks.
One product I have used consistantly over the years is J-B Weld (see jbweld.com). It is a two part epoxy and once hardened you can drill, grind or machine it. Works great on engine cases.
If you do the epoxy bridge method you could use a very fine gauze on the inside (so it does not catch the flywheel) and build up with epoxy liquid metal. I am guessing that as the damage is next to the mounting rubber and therefore bolt hole??
If it is it will always be weak and probably flex which will mean the epoxy plate will fall out when the bash plate is next whacked hard. A flexible method may be better but I can't think of a decent method just now.
Welding crankcases can be difficult. It can warp them and cause problems with fitment against the other half, and also bearing seating etc.
It can be helped by pre heating the cases before welding to help spread the heat dispersion. If you are missing a whole section, it will require a lot of welding to build up the missing area, and this will generate a LOT of heat. If you want to attempt it, I would personally split and strip down the case half.
Make sure you find a good TIG welder, and discuss your concerns about warping.
On the other hand...that is a lot of work. I would probably look into a way of repairing the hole with, say, a thin curved piece of alloy or plastic and epoxy metal. It only needs to stop dirt getting in. I have a 2012 evo, and the flywheel cover lets loads of water in. I just take the cover off after every trial, or wash, squirt WD40 in, blow it out with the airline and let it dry. I would make the repair on the outside though, as you dont want anything picking up on the flywheel and doing damage.
Thanks for that info. Totally agree with you regarding the welding. If it were a
I wish i had spotted it when i bought the bike but i didn't. There is about an inch square missing from the bottom outer edge of my right hand crankcase where the flywheel cover meets the crankcase. Bike is an 04 125 Beta. What would people recommend to fix it ? Could the case be welded in situ or would the case have to be split and then welded ? Anybody had any success with chemical metal type materials ? Any ideas would be most appreciated. Gareth
Ive got an 04 125 Beta Rev. Was just wondering whether other rev / techno / evo crankcase's would fit my bike. My right hand side one by the flywheel has taken a bashing and may need replacing / welding. IM hoping due to the age of the bike i may be able to pick up a used one. Does the 125 have the same cases as the 250 ?
I thik the rev3 125 have the VHST. The ports should be linked together but there must be a breather hole in the tube under the carb. It use an idle mixture screw, not an air screw. More turns out is richer mixture at idle. Normally it would be around 1 1/2 turns out.
Vent tubes have to vent. Just cut a hole in the middle of the two!
Couldn't agree more. I wouldn't be surprised if i have to adjust the air screw once the system is vented rather than closed. Is it still 2 1\2 turns out approx on these little 125's ?
Just stripping down my 05 rev3 125 after buying it. Its the turn of the carb now. Intrigued as to why the two carb breathing pipes are linked together onto each other. Firstly are these breather or overflow pipes ? Secondly should they be linked or independent?
Tried the air impact gun and still nothing. I think its going to have to be drilled out and pressed out. Definitely an engineering job. May leave it a while as the bearing is fine and i cant see me having the bike for too long. Just annoying as poor maintenance by the previous owners have caused this.
Update. Heated nut up to cherry red and the damn thing still won't shift. I've got a horrible feeling the whole bolt is seized in both the steel collar of the shock as well as the nut. The guys in the workshop are going to try an air impact type tool next.
It's pretty straight forward, you spin off the adjusters and the spring comes off
But measure your installed spring length first so you can set preload back in the same place
Just been looking at the shock. If you spin off the adjusters they would then have to pass over the larger body of the shock. How do you get this bit off ?
think your missing the point the shock isnt suppose to shock it in any direction it is to break the seal inbetween bolt and nut if you have a handheld impact driver that could help though
You cant shock the nut by doing that as the nut is not fixed to the swing arm. If the back of the nut was against the swingarm you could.
see if can file grind the shank flat and give it a good bray into the allen head wear goggles just incase then put a 6 sided socket on the shank bray and turn at same time ,you need to get shock into it
I agree it needs shock but it may be difficult to do. The nut at the back of the bolt is not pressed up against the direction of force if you shock the bolt.
leave it to soak for a while then if you have an allen bit in the bolt or even a drift in the allen head and beat it with a hammer to get some shock through it ,if you can turn the bolt whilst someone can hit the tool or even the nut to shock it whilst trying to turn it it should undoe failing this it will need heating
Thanks for that. I will let it soak over night. Just tried it again. This time I put the allen key itself in the vice and tried to rotate the swing arm. It is so seized I snapped the damn allen key. Patience is needed.
Rev3 125 High Revs When Choked
in Beta
Posted
Hello again. I know the choke on a cold engine causes higher rpm but mine revs so high when the choke is on I worry its ruining the engine. When the choke is then switched off the revs are fine. It certainly isn't healthy for a cold engine to rev that high. Carb is a dellorto. All the inlet rubbers are new so i don't think its an air leak. Could the choke itself be worn causing this high revving. Carb has been stripped-down and rebuilt. Any ideas ?