Topic: Anybody have experiance w/ these Yosh carbs?

[736cc]

Yamiya carries these delicious-looking Yoshimura carbs. Anybody have experiance w/ these carbs? I want something streetable on a built motor. Recomendations?
http://www.yamiya750.com/index.php?main_page=product_info&cPath=139&products_id=1539

[MRieck]

These   http://www.yamiya750.com/index.php?main_page=product_info&cPath=139&products_id=1539

 I have a set of the TM's but not the MJN model. I have not hooked them up yet so I have no info on jetting etc. the MJN can work well....I have worked with them on Earlier GSXR's. they are different. The throttle pull is so smooth and easy on those carbs you have to feel it to believe it. They are also expensive.

[turboguzzi]

cant really understand how they can charge 240K yen / 3K$ for a set of TMR's.......

would get 'cheapo' CR's and invest the change in other stuff

[kmb69]

Mike, What is the difference between the TM's, TMR's, and the MJN models? Keith

[MRieck]

Keith
 I have the TMR's....I just shortened the designation. The MJN ( multi jet needle) carbs use a perforated tube that raises out of the needle jet (as opposed to a solid needle) and introduces fuel into the intake tract. Lifting the tube more exposed more holes which put more fuel in. Lowering it had the opposte effect. Yosh ( Fujio) came up with it maybe 15 years ago or so. It is supposed to atomize fuel better.
 The system worked OK once you got used to it. With the mainstream introduction of FI( about the best atomization you can get) the MJN just kind of died.

[MRieck]

cant really understand how they can charge 240K yen / 3K$ for a set of TMR's.......

would get 'cheapo' CR's and invest the change in other stuff

TG.....They just type in 240K yen, 3,000.00 USA  2000.00 Euro It's all keystrokes baby.

[754]

 Is that like an emulsion tube ? like the Webers have used for better atomization, the last 40 years?

[BLUE71TURBO]

 Mikuni 29mm smoothbores are the way to go, but that is my opinion for what it's worth. Way cheaper than $ 3,000.00 !!   

[MRieck]

Is that like an emulsion tube ? like the Webers have used for better atomization, the last 40 years?

http://www.google.com/imgres?imgurl=http://j-mart.biz/j-parts/images/Yoshimura/758-404-1100.jpg&imgrefurl=http://j-mart.biz/j-parts/index.php?main_page%3Dindex%26manufacturers_id%3D21%26sort%3D2d%26page%3D3&h=600&w=800&sz=329&tbnid=aC9akkDxYhoRVM:&tbnh=103&tbnw=137&prev=/search%3Fq%3Dyoshimura%2BMJN%2Bpicture%26tbm%3Disch%26tbo%3Du&zoom=1&q=yoshimura+MJN+picture&docid=s1F-0tG6TkhTcM&sa=X&ei=dDyoT92OGsrF6QHTpvy5BA&ved=0CG4Q9QEwAw&dur=5090

[johno]

   Fair dinkum you blokes, this thread has done my head in. How am I supposed to sleep tonight after seeing these carbs, I shaking with excitement.,Not cheap but look a tad special to me. Looking at the float bowl angle makes me think of the raised port.  Yeah I flowed it last night , just thinking about it before I post, but had to go to Bear territory today until Friday , spoke with Bear and will meet his swinger and crew at their bike club on Thursday for a cuppa tea and a yarn, I think Bear should be worried it might turn into a roasting of him.

#$%*e those carbs are nice, thanks for the post , i,m in Yoshy heaven now.
cheers Johno

[754]

 That link took me to a Yoshi catalog page?
 I would add a supercharger, before (rather than) spending 3K on carbs...

[MRieck]

That link took me to a Yoshi catalog page?
 I would add a supercharger, before (rather than) spending 3K on carbs...

Correct. It should show the "needle" needle jet, pilot and main jet. Somebody is making new superchargers?? Or do you mean 70's parts?

[754]

 The first page, linked to another, then a language reader box popped up then a catalogue page showed up..probably just this computer.
 FAGEOL superchargers, can probably get you ibto a charger and drive snout, for around 2K or less, in varying sizes. Serpentine pulleys are easy to make on even a small lathe..

 Webers have about 7 changeable jeeting variables, cover the range better and make it easier to correct stumbing problems that occur at sertain throttle positions.. that often plague other modified bikes with carbs. They are probably not for everyone, but they offer more changeability and solutions than most carbs... closet thing to fuel injection..they still say..

[MRieck]

http://j-mart.biz/j-parts/images/Yoshimura/758-404-1100.jpg

[754]

 Now I can see it, is the long tube used in place of the  conventional needle?

[MRieck]

Now I can see it, is the long tube used in place of the  conventional needle?

Yes. The holes are pretty small. It is adjustable for height which is easy to see. Those MJN costs about 700.00 more than the regular TMR carbs. Yosh anodizes the main jet nut, red wrinkles the tops and appears to hard anodize the bodies. Oh yeah....you get that Yosh badge on the side.    Air filter adapters are available but add to the price. You have to feel the throttle pull to appreciate it. Half the resistance than FCR carbs which are fairly light.

[Greggo]

They look delicious, and I bet they're worth every penny if you've got 'em. 

[PeWe]

Anyone that have seen these carbs on sale in Europe or US?

They really create I WANT to buy these feeling.
They must be available in numbers when they still are on the Yoshi site http://shop.yoshimura-jp.com/en/product/syousai.php?id=13653

The pricing at yamiya750.com is generally very high. Some parts double price compared with others.
I cannot see why they should cost that much more than a set of Keihin CR31. Max $1000.

It look like I have to make my old (one season used) Mikuni VM29's to fit OEM inlet rubbers. Make a shorter throttle shaft when the rack is shortened and welded together between carb 2-3.

[Jim F]

and I just paid $700.00 for a new set of RS 36 Flat slides
still way cheaper than the stuff out of japan

[PeWe]

and I just paid $700.00 for a new set of RS 36 Flat slides
still way cheaper than the stuff out of japan

Much job to get it to fit?   CB750 OEM inlet rubbers?
Maybe 36mm is a little bit too much for street use?   (836cc, ported head, 34mm inlet valves, CycleX CX-7 cam)
Flatslide 36 might have a smaller brother like 32mm that can be found as a direct bolt-on kit?

[MRieck]

and I just paid $700.00 for a new set of RS 36 Flat slides
still way cheaper than the stuff out of japan

Much job to get it to fit?   CB750 OEM inlet rubbers?
Maybe 36mm is a little bit too much for street use?   (836cc, ported head, 34mm inlet valves, CycleX CX-7 cam)
Flatslide 36 might have a smaller brother like 32mm that can be found as a direct bolt-on kit?

There are a number of guys using the RS34's (including me). They do fit the OEM insulators but it is a bit of a job to get them on. Have to use new insulators, chamfer the the ID carb side and grind down the raised sealing ring in there.

[Jim F]

should have been more specific on what bike the 36s went on
Its my GS1100 with a 2mm over big bore kit, ported head, cams
I have a set of 34s on my other Suzuki and
a set of 32s for my old 836 motor but is now a turbo with a 43mm flat slide
and a set of 29s

sorry for the confusion and yes the 36s would be to big for an 836 configuration

Jim

[PeWe]

and I just paid $700.00 for a new set of RS 36 Flat slides
still way cheaper than the stuff out of japan

Much job to get it to fit?   CB750 OEM inlet rubbers?
Maybe 36mm is a little bit too much for street use?   (836cc, ported head, 34mm inlet valves, CycleX CX-7 cam)
Flatslide 36 might have a smaller brother like 32mm that can be found as a direct bolt-on kit?

There are a number of guys using the RS34's (including me). They do fit the OEM insulators but it is a bit of a job to get them on. Have to use new insulators, chamfer the the ID carb side and grind down the raised sealing ring in there.

OK, thanks for sharing your experience. But you might have a little bit more upgrades that will need bigger carbs?
I'm thinking about how the engine will rev up from low rpm's with nice torque. 34mm's will be a better choice than 32 with my engine?

EDIT: I found this very interesting thread http://forums.sohc4.net/index.php?topic=85462.0