mcman56

Has anyone found a small battery powered fan that could be mounted to one of the vents in the Airoh? I have looked but found nothing.

I have made bushings for Sherco and Gas Gas out of 660 bronze. There is room to install grease fittings and without seals you can flush the bushings with grease like old usa cars. This eliminates the need to disassemble to grease. I notice no difference in friction but am no high level rider either.

The R37 may be a casting number used by the manufacturer who cast the cylinder. Rev3s have a 2 digit cast number that appears to represent the year the casting mold was made. They tend to show a number 1 or 2 years older than the bike. It probably depends on how quickly a cylinder can go from making the mold to getting delivered on a bike plus what ever inventory is held.

Removing 2 grams of wire will let me get up obstacles 1 foot taller....won't it?

Any update?

I had this with a rev 3 and after pulling the forks off could see the fork tubes were moving in the clamps a little bit. I polished with scotchbright, cleaned throughly, reassembled, torqued to specification and the sound was gone. A couple of years later, a similar sound came back and it turned out to be a loose nut on the top of the steeing stem.

I have painted the springs on original Reflex shocks with good results and no flaking. I sand blasted them first and then used standard rustolem spray primer and paint. Getting paint to stick to chrome may be mre difficult.

Do you really have to remove the mid muffler to get the air box out on a 2008 rev3 200?

http://www.ebay.co.uk/itm/261981283404

The other CDI has no curve and the bike runs the same. I still do not know if the OEM CDI should have a curve or not. The aftermarket was on: http://www.regulatorrectifier.com/catalog/20032008-Beta-250-Rev-3-CDI-Unit-1

The aftermarket one is a combo CDI/ coil but has the same lack of a curve. The Beta CDI has 4 wires vs the 6 wires I have seen on a diagram listed by Dan W. There is one two pin connector and two seperate wires, one of which looks like the kill button connection.

I have found a couple of advance curves on line for trials bikes, one for Beta and one for Sherco. They show curves like a 4 stroke so I guess mine should have something similar. I could not find a Beta OEM CDI online but did find an aftermarket one. They could not tell me what type of curve it has but I ordered one anyway and will see what happens. http://www.leonelli.com/english/028%20CDI%20DIGITAL/028%20INGLES/028%20VOK.E-ING.pdf

Compression is 155 psi. I measured the stroke. Beta USA was also nice enough to confirm with the factory before I did the swap. On some official Beta publications, the bore/ stroke numbers are misstated for the 200. (maybe from 2008) Working out the numbers shows that they do not equal 200. That had me confused for a while.

The problem is that I have already barked up every tree I can find. It has the fast throttle. Carb cleaning, carb jetting rich to lean, OEM and Boysen Reeds, Keihin 28 and OKO 26, pack muffler, inspect head pipe, alter static timing at stator and probably a number of things I can not remember at the moment. Some of these had an effect but still did not change the basic flavor. The advance curve thing is one thing I had not considered. Maybe I'll try a CDI from a bike breaker. Actually, it is a very sweet bike, perfect for a rider that takes points in turns due less that perfect throttle control. (starts easy, etc.) I'm just at point where I could use better response.

The Beta 200 is a sleeved down 250 not a big bore 125. At one point I actually split the cases to see if there were any stuffers in the crank but there are none. As far as I can tell, the only difference in the crank assembly is that the 200 assembly has a bronze bushing in the small end of the rod to size it down for the smaller gudgeon pin of the 200. The Gas Gas 200 (175) is a big bore 125. I believe Sherco is/ was the same.

Looking at the parts list, all ignition, intake and exhaust components are the same for the 200 and 250. I bought the 250 top end on ebay so am not sure of the year. There is one thing I have never been able to figure out. Beta used to sell 270 kits for the 250 Rev3s but there were several different versions depending on the model year. Externally, all of the Rev3 top ends I have seen look the same reguardless of year so I don't know why there were different kits.

Here is the stator. There seems to be more than one brand of ignition on Betas. I believe this one was made in Slovenia. It has been rewound since the picture. I have heard that all lignitions with triggering coils have an advance curve . This is a 2008 200 with a 250 top end installed.

I have an 08 Beta Rev3 250 with poor throttle response. (much much softer than a well worn GG200) I have tried all sorts of things and someone on here suggested that there could be an issue with the ignition advance curve. I ran a timing light and got 15 degress BTDC at idle and reved up got 20 degrees. This seems like too much advance at idle and I believe 5 degrees of additional advance is a byproduct of the circuit and not a planned advance curve. For comparison, I once did this on a 97 techno and got 6 degrees at idle, 20 at mid range and 25 to 30 at full scream. I can't find a specification for this anywhere. Does anyone know what it should be? I'm wondering if the CDI is bad and stuck at semi full advance. I hate to buy a new one and find out that they are that way by design.

I ran a timing light on it and got a very odd result. Idle is about 15 degrees BTDC. Reving up the engine pushes this up to 20 degrees BTDC where is stays. Could this mean the CDI is locked in full advance mode? Does anyone know what this should be like? I have to run rich to avoid pinking when just creeping along. I checked this a long time ago on a 97 Techno and got 6 degrees at idle, 20 at mid range and 25 to 30 at full scream.

My only Beta comparison is a 2014 Evo 300 Factory. Throttle response is much much better on the 300. I'll try a timing light and see if there is any advance. A CDI is $255 US so a bit expensive to try.

I don't understand the statment about a site glass. This has the standard plastic cover over the flywheel. I'll try it with a strobe. If it is an advance problem, is it the CDI unit that is bad or could it be somthing else?

There is no flywheel weight.

I have a 250 Rev three and the response (pick up) of off idle is very very soft. It there anything that can be done to improve? It does not feel weak in that it will pull tall gears at low revs but the engine just winds up very slowly. A GG200 has significantly quicker response. This is a 2008 with later 250 top end. Timing is on the advanced side. I have run a 28 mm Keihin and 26 mm OKO and it is the same. Jetting richer and leaner does not alter the response much. I have also run Boysen dual stage reeds and OEM Beta reeds but it still feels the same.

What does teg GB flywheel cost?

I tried a boost bottle on on a Rev 3 and it did have some effect. I would not say there was more power but it would take very large throttle openings at low rpms and condinue to pull cleaning.