What type of air filters are you using? Any vacuum leaks? What is the condition of the carb to engine rubbers? Could the accelerator pump be squirting too much fuel when cracking the throttle open? Just a shot in the dark.

Do a search in this forum for flat slide carbs. You may find some information that will help you out. I think the Keihin FCRs are a more common swap, but there may be info on the Mikunis also.

 

Thank you!

What type of air filters are you using? Any vacuum leaks? What is the condition of the carb to engine rubbers? Could the accelerator pump be squirting too much fuel when cracking the throttle open? Just a shot in the dark.

I am running stock airbox with a brand new K&N air filter since that was the only filter available near me. The Carb isolators are brand new from Triumph and were a while you were in there job, so i can't imagine there would be any vacuum leaks. It is possible that there is too much fuel from the accelerators, but i did play around with the activation point and didn't seem to make really any difference.

 

Yeah, all these CV carbs are sensitive to the intake configuration. You need either the stock airbox setup or the one recommended by Mikuni if they don't call for the stock setup. That off-idle area is the hardest to tune for as the carb is transitioning from the idle circuit to CV mode.

 

Thank you,

all these CV carbs

These carbs are not CV, they are just regular flat slide carbs with an accelerator pump. They are not stock.

https://mikunioz.com/shop/mikuni-rs-36mm-carb-kit-for-honda-cb-2/?v=5435c69ed3bc

 

If it's the accelerator, any suggestions on how I can go about turning it? I've gone through and adjusted it in incriments from full squirt to no squirts without any meaningful change in how the bike responds

 

"bolt-on and ride"

Talk to whoever made that statement.

The Keihins are pretty common. You could probably find a used set with good seats on ebay... Even if it's not exactly the same, you could swap parts from yours to make them work.

 

I've been talking with the mikuni dealer I bought them from out in Australia (I'm in Canada), they've been helpful in attempting to find the solution, but less than helpful in actually getting them to work.
This has been a 3 year saga with a 2000$ investment so far, and trying to find the keihins on eBay has been very difficult. Especially because the needle seats are physically not replaceable

So at this point I'm invested in getting the mikunis working.

 

Are these what you were looking for? I have this set which appears to be used but unmolested I pulled the float bowls and they are clean. The vacuum diaphragms are all good as well. If you are interested maybe we can make a deal?

 

Those look in amazing shape! I don't know if I wanted to make an investment in another set of carbs considering how much the mikunis have drained from my bank (but I may be living in a sunken cost fallacy at the moment).

But I think for the right price we could possibly make a deal.

Let me know what your looking to get for them. Feel free to PM me if it's easier.

Much appreciated!

 

I got your PM and I have been trying to respond! but apparently my account is under review now for some reason.

As soon as that is cleared I will be able to send my reply - I wanted to let you know so you don't think i'm ignoring you!

 

I suspect you need 10 posts before you can access the PM feature.

 

go figure-well i reached out the the ADMIN team and see what they say

 

Just a quick update for anyone who may be interested in doing the Mikuni RS36 conversion - After a bunch of trial and error, more research and consulting the most unlikely source of ChatGPT. The T-bird lives again!

I was able to take it for its first ride up the street in nearly 4 years. What a treat. The sounds of the T-birds triple with megaphone pipes is intoxicating.

As for the Mikuni's, I found the optimal setup so far (without a proper long haul test) to be:

Pilot Jet Size	#17.5
Pilot Screw	3/4 turn from lightly seated
Needle	clip in the 4th slot from the top
Accelerator Nozzle	#45
Accelerator Nozzle Lever	Adjusted to squirt immediately and end at 3/4 throttle
Main Jet	#130

Right now my only question is the Main Jet since I didn't have the space for WOT testing. I am hoping to get insurance on the bike and do some further testing and riding later this summer (fingers crossed). So far, the bike feels really responsive. I will update this table if/when any settings change based on the longer rides - my anticipation would be only the main jet at this point may change.

In terms of changes to the bike, I added a quality dual cable throttle and swapped the right switchgear out for one from a Street triple. This wasn't plug-n-play, so I did some resoldering to use the connector from the T-bird. It looks nearly OEM.

The bike is also outfitted with a set of dunstall megaphone mufflers and a stock airbox with a K&N air filter since the stock foam filter had started to crumble.

 

Quick Update:

Finally had a chance to get insurance on the bike and go for a few rips to test out some different sized main jets, but between fatherly duties, bad weather and other responsibilities its been slow goings.

With that said, I think I have finally narrowed down the ideal settings for my current set up - K&N style air filter and stock airbox with free flowing Dunstall megaphone mufflers - which I'm sure would be a fairly common set up now for a lot of these older bikes.

Below is an updated table of the setting that I have landed on.

Pilot Jet Size	#17.5
Pilot Screw	5/8 turn from lightly seated
Needle	clip in the lowest slot (be sure not to lose the nylon spacer)
Accelerator Nozzle	#45
Accelerator Nozzle Lever	Adjusted to squirt immediately and end at 1/2 throttle
Main Jet	#110

I haven't gone on long enough ride to say 100% the proper set up, but I'm very very please so far with a few good rips up and down the road.

If anyone is curious - to verify my carb settings I have a janky set up of some car exhaust piping, a wide band O2 sensor and a silicone coupling holding it all together. I put it on the left exhaust since only one cylinder fires through it which reduces the data error for me making slight adjustments. I can then pattern these settings to the other two carbs once please with the results.

I aimed to keep the AFR between 13.5 and 15 when at running temps.

I hope this is helpful for anyone looking to install a set of these Mikuni's on their triple as it has been a very expensive learning adventure for me as I have had to purchase quite a few sets of Mikuni jetting parts, not to mention the tedious amount of time installing and removing the carbs for EVERY change.

Once I get a chance to test these final settings a bit further I will report back.

Cheers!

 

Final update:

I had an opportunity to go on some longer rides and finally nailed down the top end jetting. It's still a slight bit rich, but I am very happy with the way its running and much prefer to be a bit rich than lean.

Pilot Jet Size	#17.5
Pilot Screw	5/8 turn from lightly seated
Needle	clip in the lowest slot (be sure not to lose the nylon spacer)
Accelerator Nozzle	#45
Accelerator Nozzle Lever	Adjusted to squirt immediately and end at 1/2 throttle
Main Jet	#107.5 - could get away with a #105

I hope this info helps anyone who is looking to make the Mikuni RS change to their t-bird.

Happy Riding all!