Mikuni experts, your answers please...

[stigonpaso]

Sounds a good plan.


You'll be saving a few Watts for your battery, ignition and head light going to a vacuum fuel pump. The hexagonal pump flows heaps at a safe 3psi. Its a high flow rate at low pressure.

Would this work? I looking for a fuel pump myself. Thanks for the idea Koko64

http://www.powersportsplace.com/parts/m ... /overview/

[lane1feathers]

Hmmm, maybe it's not too late to make the mods to weber?

[paso750]

stig 14lph is too little. Those pumps are often used on scooters.
http://www.mikuni.com/c-fuel_pumps.html
DF52-136 and DF62-702 look like the ones that can be found on the Yamaha TDM/TRX and Ducati with the difference that they have 4 connections instead of three. The flow rate is at least more than double than the one in your link.
I know a couple of guys using the Yamaha fuel pump on ST2, Paso or 900 Elefant and they all run fine.

G.

[stigonpaso]

http://ca-cycleworks.com/002-220

[paso750]

odd

[koko64]

Chris is confident the small pump will work.It should empty a Monster tank in less than 1 1/2hrs. I prefer the big pump for modified large motors and pumper carbs.

I was going to use the small pump with CV carbs on a Paso, but my new bike plans are unfortunately on hold.
Ducati still sell the big pump in oem single outlet form, Mikuni sell it in dual outlet form.The rebuild kits dont cost much, but Monster guys say to get the genuine Mikuni kit.

[koko64]

Im not sure if a vacuum pulse pump works with a Weber carbs float chamber, but it works with the small individual float bowls on moto specific carbs.

[paso750]

the underpressure fuel pump of later Ducs works just fine with a Weber and some also say they feel an improvement in low end performance.

[koko64]

Was that electric or vacuum pumps? If the hex vacuum pump works with the Weber that would be cool.

I tried the little Mikuni pump on my modified Monster but it did not flow enough as G said. It struggled to refill the float bowls and accelerator pump with "heavy use". I serviced the hex pump and put it back on and have more than enough fuel.

I hope to try the little pump with some CV carbs a Paso when life allows.

[paso750]

you were talking about vacuum pumps.

G.

[koko64]

Yes, how do they work with the Weber? I have no experience with that combination. I was curious due to the Weber's float chamber.

[lane1feathers]

Progress report...
Weber out



Mikunis in!





Started this morning, rejetted the carbs with the Dynojet kit, stripped out the air box and the weber, went to install the mikunis but they wouldn't fit...coil in the way!...moved coil forward and went for 2nd attempt. Really tight fit between the frame rails, but it fit, so all good. Bolted everything down, hooked up fuel feed and vacuum hose, overflow pipe, etc., just have to connect breather hoses and route them to the little triangular plastic tank when I work out where to put it! As these Mikunis are from a TRX, the throttle cables I bought from eBay (off a 900SS) are too short....so until Monday that is as far as I can take it. I just hope the local bike shop has some cables that will fit or can make some to suit.

[paso750]

I never noticed the different coils location on a 906. On the 750 they are mounted on the vertical frame tube on the left side and on the 907ie it`s on the right side.

G.

[lane1feathers]

That was just one of the hic ups I had! The screws that held the bowl on one of them were that tight, I rounded them trying to get them out. I had to grind the heads off 3 of them with a small grinder! I replaced these with Allen Bolts.
Then, when I went to fit the inlet tube on the vertical cyl., the brass T piece I had made up for my cooling system was in the way so I had to make the hose going into the bottom of it shorter. Wasted coolant...I hate that
With the coil, I just moved it forward and secured it with one bolt (bottom hole of coil into top hole of bracket)
I tried to make the cables reach, but it just wasn't going to happen.

I used the DJ needle jets and put the ring on the 4th groove from top. Swapped out the springs and used the 175 mains. Screwed out the mixture screw three and a half turns on one but couldn't adjust the other as it was locked in and I rounded the head trying to loosen. Because its buried in a fox hole I couldn't get at it. Best option would be to drill it out but upon inspection it looks to be screwed in the same amount as the other one (at 3 1/2 turns) so I hope the mixture will be right...if not, out it comes.

Does anyone know if there are any 'off the shelf' cables that are identical to the 900ss only 40cm longer? If not I'll have to get some made up.

[Derek]

Does anyone know if there are any 'off the shelf' cables that are identical to the 900ss only 40cm longer? If not I'll have to get some made up.

Monster maybe, but 40cm is an awful lot longer.