Jump to content

Boyesen Dual Stage Reeds


the addict
 Share

Recommended Posts

 

  • Replies 44
  • Created
  • Last Reply

Top Posters In This Topic

I too purchased some boyesen reeds and to be honest they did not make too much of a difference when out on the bike. The exhaust sounded a bit dull and the bike was a little more resposive other than that not much really. I have come to the conclusion that this was all down to me running the bike too rich. Now i have changed my jets the bike has been transformed!

My advice - if you are buying boyesens then think about your jets too!

I am currently running:

BPR5ES Plug - Lampkins recommended this plug. I was running BP7ES and I was told by Lampkins this was designed for the Spanish summer!

145 Main Jet

27.5 Pilot

Removed flywheel weight

Boyesen Reeds

I have gone from a black oily plug constantly fouling to a nice brown coloured plug! :thumbup: I am wearing my smug look!...for now

Link to comment
Share on other sites

 
  • 4 weeks later...
 
 
 
 

Hi All. :beer:

I ride an 07 270. First I did the float height mod, and this made a difference to how the bike ran, a little leaner (maybe in my head but...), however this did fix any overflow.

Second I ordered a 27.5 pilot and a 145 main jet, put them both in and thought that I had lost a little power at the top end of the rev range, so I put the 150 back in. The running effect of this was that it a bit was crisper off the bottom end. Also prior to this I had some spark plug fouling issues as well, though I think there is about a 75% chance this was a bad fuel batch.

In search of a better throttle response, next I advanced the timing by about 2 mm at the adjusting screws, and the response was much, much improved. Thinking WOW! "I want more of this..." I went another 2 mm. I feel obliged to mention at this point that I run 98RON fuel. The result of this second advance of the timing was a MASSIVE increase in torque off the bottom end, and generally more power across the range. I left the timing there.

About this point I thought that I noticed some fuel starving when the bike was "wedged" with the front wheel quite high, so I installed the float bowl extension, I am confident this has cured that problem.

Next I installed the boyesen dual stage reeds, In hope of more throttle response however that was not to be. :D But the engine did rev out stronger, and I thought that the plug was sufficiently dark to warrant re-installing the 145 main jet. After installing the 145 main jet, the bike has improved in the upper mid to very high rev range. quicker, and revs out much better when you really want it (big revs :D ).

So in conclusion, and for those desiring more power, I would suggest that the most value is in advancing the timing, second in finding the best possible jetting. third for me (but mine was not stalling when facing down hill) - best float height. Fourth the Boyesen reeds. And fifth the float bowl extension.

Who can tell me what the gains are like with the high compression head? please.....

Oh and has anyone secured a suitable 2.5 throttle slide (stock is a 2.0)?

Cheers!

Link to comment
Share on other sites

 
 

My boyesen reeds turned up today and i wondered how many of you have had to move your needle jet at the moment im running

float bowl extension

carb drilling mods

ngk iradium plug

145 main jet

27.5 pilot jet

jitsie air filter

boyessens ready to be fit!

Link to comment
Share on other sites

 
My boyesen reeds turned up today and i wondered how many of you have had to move your needle jet at the moment im running

float bowl extension

carb drilling mods

ngk iradium plug

145 main jet

27.5 pilot jet

jitsie air filter

boyessens ready to be fit!

ive recently fitted boyesens to my 06 270,much better response and much harder to stall,well worth the cash,as for the needle jet i left mine as it was and it runs spot on

Link to comment
Share on other sites

 

Tone, to advance the timing remove the flywheel and you'll see the stator plate. Loosen the three screws and rotate the plate counter clockwise to advance the timing. Here's a pic: Ign00_02.jpg As for how far to advace it I'll let those that know for sure advise on that. My bike is an 02 270 and found this picture. When I pulled my flywheel the stator was rotate CCW so the screw head was about 1/4 of the distance into the area between the red lines. Bike runs great. Greg

Link to comment
Share on other sites

 
 

My boyesen reeds are in and what a diference seems to rev so much better and cleaner! And thats only riding up and down road? I also thought about removing flywheel weight but i bottled it.I must be getting soft in my old age!

Link to comment
Share on other sites

 
My boyesen reeds are in and what a diference seems to rev so much better and cleaner! And thats only riding up and down road? I also thought about removing flywheel weight but i bottled it.I must be getting soft in my old age!

You must do it itactually makes it even smoother, I removed mine and after a little while went for a quick action throttle and really pleased, not a handfull at all really smooth and progressive.

Give it a go

Tone

Link to comment
Share on other sites

 

I've a 2007 250 and fitted the boyesen reeds. I didn't loctite the screws as they fitted very tight to reed block casing. The reeds came with fitting instructions saying to turn the air screw 1/4 or 1/2 turn which i done. I kicked the bike over and had the throttle closed with no choke, it started first kick and ticked-over without any unwanted revving to keep the bike from stalling - something the bike would never do with the standard reeds. I ran the bike down an alley way and it revved great, clean pick up from the bottom end and revved a lot easier. I've not altered the jetting,and its got a flywheel weight with a slow action throttle. My intention was only to have the bike revving more freely at the bottom end and no power gains!!! Todate the boyesen reeds have done the job.

Edited by spud
Link to comment
Share on other sites

 

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
 Share


×
  • Create New...