How to sync my aftermarket carbs?

[littleroot]

Tom MLC was going to help me sync my carbs but he said I should ask for tips here because he has never worked on my type.

Total virgin to engine work I have no idea other than brand name Mikuni and they do look different than the ones in the manual.

Many thanks in advance for anything you can tell us.

-Bob

Close up shot here, more, highres photos in the link in my signature.

[posplayr]

Those look like RS flatslides which are expensive carbs. Do you have push pull (dual ) throttle cables?

Those carbs generally go for about $400 depending upon the size. 36 and 38mm are popular

[littleroot]

Push-pull=yes

Yep, it has push/pull cables. Looks like factory/original throttle system, or so I thought. Another friend did mention that being a problem with performance and I might want to look at going to a standard system for better response(?). Seems to me there is a dead area in the cable, or a bit of "play" from released to power-on, but not having driven any other bike I would not know better.

Thanks for the response!
-Bob

[littleroot]

Needs push/pull

Yep, it has push/pull cables. Looks like factory/original throttle system, or so I thought. Another friend did mention that being a problem with performance and I might want to look at going to a standard system for better response(?). Seems to me there is a dead area in the cable, or a bit of "play" from released to power-on, but not having driven any other bike I would not know better.

Thanks for the response!
-Bob

Just read up a bit on the RS Flatsides: requires push/pull cable.

[Dave8338]

Just read up a bit on the RS Flatsides: requires push/pull cable.

I was just going to mention that. Duals for those carbs is the ONLY way to go!!!!

Nice rack-O-carbs, for sure! Are you going to replace all the screws with torx or hex stainless?

[doctorgonzo]

Dang, a set of those is high on my wishlist!

[Larry D]

Okay....somebody explain to me why. Why are these carbs so sought after ? How are they better ?

[doctorgonzo]

Okay....somebody explain to me why. Why are these carbs so sought after ? How are they better ?

Some carb geek will know better than me, but my understanding is quicker response. I'm sure there are others as well. There is a reason new bikes all have flatslide instead of CV. It's just "newer" carb technology.

[don_gibb6512]

Okay....somebody explain to me why. Why are these carbs so sought after ? How are they better ?

Someone like RapidRay would have all the details but basically the RS carbs are mechanical, used mostly for racing because you have instant response from the throttle. The main jets can easily be replaced without removing the carbs and have an adjustable accelerator (fuel) pump that jets fuel from the intake side of the carbs in to the throat giving a real kick to acceleration. They come in sizes 34mm, 36mm, 38mm and higher but when you get in to the 40mm and up you're overall ride abilty takes a serious dive. If you want an overall smooth ride and aren't a real acceleration junkie, stay with CV carbs.

[rapidray]

Bob, if you want, give me a call at 714-356-7845. Ray.

[Tom MLC]

Isleofman, thanks for the detailed response. When the time comes to sync Bob's flatslides, we'll be using a Morgan Carbtune and a Colortune. Only the best will do! The procedure sounds much the same as my CV34's.

2500 rpm, eh? I wonder why? I usually sync my carbs at around 4000 (even tho the manual says otherwise). I (we) may give Ray a call one of these days.

In my opinion Bob's bike is running a bit lean. His pipes are blue, and his plugs are white. Post those pics Bob. He's running B7ES plugs that the PO installed. Any comments on that?

[salty_monk]

A colder plug.. doesn't make too much sense if no other mods. Normally you'd run a colder plug for track use or something.

Dan :_

[littleroot]

This seems to support how my bike runs: it likes to go fast and spits an coughs sometimes when I want to cruise along in the 3000-4000 range.

I would like to adjust the jets to cure the lean condition but I cannot find a manual online. The manufacturer seems to have pulled it.

Can anyone help me find docs on these Mikuni flat slides carbs?

Thanks,
-Bob

Someone like RapidRay would have all the details but basically the RS carbs are mechanical, used mostly for racing because you have instant response from the throttle. The main jets can easily be replaced without removing the carbs and have an adjustable accelerator (fuel) pump that jets fuel from the intake side of the carbs in to the throat giving a real kick to acceleration. They come in sizes 34mm, 36mm, 38mm and higher but when you get in to the 40mm and up you're overall ride abilty takes a serious dive. If you want an overall smooth ride and aren't a real acceleration junkie, stay with CV carbs.

[Mysuzyq]

I would like to adjust the jets to cure the lean condition but I cannot find a manual online. The manufacturer seems to have pulled it.

Can anyone help me find docs on these Mikuni flat slides carbs?

Thanks,
-Bob

I'm guessing you have the 36mm (D3K) RS on your bike. Best way to proceed IMHO, would be to check that the jet sizes and settings currently in your carbs confirm to the info provided by Mikuni, for your specific application (GS1100), in the table posted by Isleoman. I have the same info too....maybe a bit easier to read.

http://www.carbparts.com/mikuni/mikuni_rs_standard_tuning_specif.htm

I plan on using the recommended jets and settings as a baseline, and tune from there, if necessary.

Tony.

[Rodman]

your gonna tune those carbs just like the old mechnical carbs like on my 77 gs 750 ,they are the mic mechanical [imo the best . easiest to work on and no expencive rubbers to mess with ] those carbs dont belong on that bike and im sure youll be happy with them but they would be much better on mine .lol really nice set . they will really wake up that bike . smooth as glass if correct , very good throttle responce and smooth all the way through the twist of the wrist

Rodman