betarev3 Posted November 3, 2007 Report Share Posted November 3, 2007 Hi - is it necessary to replace the reed blocks after so much service as a routine operation or not? If not routine, then how do you know when to change them? should they be inspected routinely? do I need new gaskets to do this or can you re-use? Are there upgraded types available and are they any good? What differences would be noticed? Thanks, Laurie. Quote Link to comment Share on other sites More sharing options...
jezza Posted November 3, 2007 Report Share Posted November 3, 2007 The reed block is made up of reed petals attached to the block and the amount they can flex is limited by a rev plate. As with all things the engine will benefit from a fresh pair of petals from time to time, probably when the top end of the engine is done would be a good guide. Boyesen do a set of dual stage reeds which run with a rev plate which is different to the standard Beta one. Also instead of one petal top and bottom the Boyesens have two top and bottom which open at different stages as their name suggests. They are easy to fit and retail at about Quote Link to comment Share on other sites More sharing options...
betarev3 Posted November 3, 2007 Author Report Share Posted November 3, 2007 Thanks very much for the prompt reply - I'm on a steep learning curve re. trials and there is a lot to get to grips with (sic). I will probably leave it for a while and concentrate on riding technique for now. Cheers, Laurie. Quote Link to comment Share on other sites More sharing options...
paul w Posted November 3, 2007 Report Share Posted November 3, 2007 You may have to re-jet your carb afterwards to fine tune and get the best out of them, all this is explained in the instructions and the diagrams which come with them, usually they will make your bike run leaner on the pilot jet and slightly richer on the main jet. i fitted Boyesen reeds and re-jeted last year, just for comparison , jezza, where did you end up on the sizes? and who gave you the info on change ect? cheers paul Quote Link to comment Share on other sites More sharing options...
jezza Posted November 3, 2007 Report Share Posted November 3, 2007 The info was in the instructions that came with the reeds. I found my bike went best with the needle set one notch leaner on standard jetting and running a BP5ES plug. Nice plug colour at full throttle and at usual plodding. PW what did you end up running? Quote Link to comment Share on other sites More sharing options...
paul w Posted November 3, 2007 Report Share Posted November 3, 2007 i went to a 27.5 pilot, found that the needle worked best in the middle and went down one size on the main. i set the air screw when the bike was hot and i think its about 2 1/4 out. plug and piston top are great on colour. takes some warming up but is so crisp when hot and pulls from tickover. from what i can gather 250 beta's can be all over the place on carb settings, mine was not at all good from new. i am going to be getting an 08 soon so we will have to see what happens with that. Quote Link to comment Share on other sites More sharing options...
dan williams Posted November 3, 2007 Report Share Posted November 3, 2007 I run the VForce on my 270 and have the needle in the middle, 27.5 pilot and 145 main. The plug shows some residue from the Cam2 race gas (doesn't run as clean as VP C12 but is cheaper) There isn't much difference on top from the stock reeds (not like I could tell anyway since full throttle is the abode of trials gods and frightening to us mere mortals) but the bike will pull a taller gear at low revs. I can climb really slooooow when I need to. In a nutshell I think the VForce3s were a great investment on my '02 and '05 and since I'm seriously considering an '08 I'll put them on that too. I've run reeds for years and never replaced them. Unless they are visibly frayed or fractured they are probably OK. The spring tension on the reeds isn't what holds them closed. It's the reverse pressure in the inlet tract that closes the reeds. Even a reed that doesn't make a perfect seal is still going to let only a tiny amount of fuel air charge back into the carb throat at the lowest RPM. Unless you can see physical damage to the reeds or seats they're probably fine. One thing to note though is the stock Beta reeds,at least on my '02, are fiberglass. Yeah I know they're painted black to look like carbon but I've had them under a microscope and the fibers are clear. Of course if you're like me you'll just replace them for peace of mind because once it's apart it's a cheap way to feel good about your baby. Dan Quote Link to comment Share on other sites More sharing options...
slapshot 3 Posted November 3, 2007 Report Share Posted November 3, 2007 Boyesen Reeds, 27.5/145 jets mixture screw 1.75 turns out, couple of minutes warming up gently and as they say robert is your fathers brother!!! everything a lovely sandy brown colour and It don't leak fuel either...sorted Quote Link to comment Share on other sites More sharing options...
slapshot 3 Posted November 4, 2007 Report Share Posted November 4, 2007 Boyesen Reeds, 27.5/145 jets mixture screw 1.75 turns out, couple of minutes warming up gently and as they say robert is your fathers brother!!! everything a lovely sandy brown colour and It don't leak fuel either...sorted *&%king typical, I go and type that and what happens today, carb starts pi$$ing fuel everywhere. Time for a strip down anyway be lucky of I get out much before Feb so I'll get a few bits and piece done....Fixing the *&%$ Quote Link to comment Share on other sites More sharing options...
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