Trouble tuning Mikunis

[Foxtee]

Hi Mc
I´ve got the valves on order (3-4 weeks) but I´ll hunt round ebay for tubes and an air box.
I had a VFR 700 Interceptor when i came back from the UK in the late 80s .. loved that bike still got the workshop manual

[paso750]

don`t spend your money on an SS airbox. There`s no way of fitting it. Frame and tank are completely different.
Do not run without fuel pump also. The carb stands higher than the Weber and you`ll run into problems when fuel level is low. W/o fuel pump you`ll run out of fuel when there´s still some in the tank.

G.

[Foxtee]

Thanks G
I´ve keep the fuel pump as looked like the carbs where higher , I´ve still got the engine breather box thats mounted above the rear of the motor in front of the battery box and was wondering if that would do the trick.

[Mc tool]

Hi Foxtee , I have had another look at the hoses etc. The little bulb things in the breather hoses are a filter not a valve of any sort . If I look in the hole in the end I see a mesh screen with filter material ( very much like the stuff K&N filters are made of ) and I can suck and blow both ways thru them . The triangular black thing was bolted to the frame and is nothing more than a catch bottle ( I called it a still air box )and the 2 hoses just poked into 2 of the holes


My SS ran well with no cover at all on the air box, I know the jetting aint standard but I cant remember what it is , but can have a look see if you want ( also had stilmotor exhausts ) not sure why the jetting was changed

[Foxtee]

Thanks Mc
For the pic´s I´ve got the valve-filters on order at Motomart the local Ducati dealer I printed off the pic Micklm posted to show them what I was after, the description on their system said filter .
But it looks like I can put them on and just run the hoses away from the hot bits without anything else.
I´ll stick with the Dynojet stage 1 kit from what I´ve read it should work.

[Mc tool]

I think those filters are used more as a dampner and with that in mind I'd still want to put the hoses in a catch bottle , more to baffle than to catch

[Mustang505]

Hi Guys
I was told the other day that you should fit a link hose between the two inlet tubes when running the Mikunis as per the Weber carb. not sure if this is fitted as standard on the Mikuni carbed models that came out later - do any of you know and if so is it important?

[Tamburinifan]

not sure if this is fitted as standard on the Mikuni carbed models that came out later -

No link, separate hoses on Monster and I`m quite sure that goes f rest of the carbed ones.

[88WhitePaso750]

My Paso has Mikuni 38 Horizontal flow flatslides and I too am having trouble dialing it in. Where did you get the manifold tubes to use downdraft carbs?

Does anyone have any experience with manifolds for slidedraft carbs, like the one that rotates the right carb into a new forward position? Any comment, manufacturers, stories would be appreciated. I am trying to make a decision on the next step to take with mine.

Chris

[micklm]

I'd still want to put the hoses in a catch bottle , more to baffle than to catch

I have to agree with this. Although I'm only repeating stuff a Duke mechanic friend once tried to explain to me (so I can't claim first hand experience) I understand that the lines that run to this little tank are actually an "atmospheric pressure sensor" of sorts.

It allows the carb mechanism to balance the intake pressure vs a static reference pressure i.e. atmospheric pressure (or something like that - others please jump in and correct me if I'm talking nonsense).

So in this case the little tank and the dampers are actually in place to ensure the air at the end of the tube is not moving as this would lead to variations in pressure at the tube opening.

i.e. still, quiet, non moving air is essential at the end of this tube otherwise the pressure varies.

Hence the little box to create a sheltered spot and the in-line dampers to further reduce the fluctuations in pressure.

Any old box would do - it doesn't have to be the OEM SS or Monster one. Just something with a sheltered volume of air and a few hole in it.

I might be wrong, but that's my 2 cents worth......

[higgy]

http://www.autotrimdesign.net/detail_JM ... ifold.html


Don't know anything else,I prefer the Weber.
http://mysite.verizon.net/vze2hw9t/index.html

[Crusher]

My Paso has Mikuni 38 Horizontal w flatslides floand I too am having trouble dialing it in. Where did you get the manifold tubes to use downdraft carbs?

Does anyone have any experience with manifolds for slidedraft carbs, like the one that rotates the right carb into a new forward position? Any comment, manufacturers, stories would be appreciated. I am trying to make a decision on the next step to take with mine.

Chris

Hi Chris I 2am running the same setup and have put the manifold on which Higgy has shown above. I think they are a good setup but still need fine tunning. I run large hex-4/042 165main jets,these might b a bit 2 rich yet. vm22/210pilot jets size22.5. Needle jets size 369 Q2 Primary type and the actual needles are a 6 series on the 3rd notch Im still having the idle problems which is why Im looking at the tudes they are talking about as ive checked air leaks,balancing,etc so I just keep chipping away at it as like you the only info seems 2b on the round slide carbs.Also run Uni pod filters from Aussie [good filters] so when it does idle it runs sweet at about 900 to 1000rpm so is all good until it sticks which is around the 3000rpm mark not so good when trying 2 burn off speed in the corner no back firing pulling like a young school boy so stick with it as like higgy has a love afair with the webber which I never got 2 experience and would have given all 2 make it work Im stuck with what I have and will go 2the end 2make them work as I like the challenge. Cheers Paul

[Foxtee]

Fitted one-way breather valves to the carbs & made a re-stricter for the fuel return line... running alot better


Now working on 17" wheel conversion nearly finished the front