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Mikuni TM Flatslides on a 77 R100/7

Dhkreitz

New member
Seems the proper jetting and details a secret on this topic? I know this is a deviant mod, but seems like there is more about how to find the right sizes for a stock motor (plug checking and stepping up jets) than other folks experiences. Has ANYONE actually put TM Mikunis on an R100/7? Rather than paying for a box of soon to be unused brass, I'd rather pay someone to just tell me the best setup for my new slides- Seeing as they did all of the work already they may as well be compensated for it.

Thanks for any help on this guys.

1977 R100/7
1968 Chevy C10 (currently my towtruck)
 

Thanks for the direction. Got the carbs from Mikey over Martindale Motorworks (great guy and shop). Seems these threads have some general like and dislike info, but no specific jetting/needle details. Been in and out of all the mikuni threads on MOA, just not finding it, hence the request for someone to impart their wisdom from experience.
 
Seems like this post indicates what came with the carb versus what is needed for operation...isn't he asking the same question as me? Happy to be corrected.

Re-reading his post more carefully, I think that may be the case.
 
I would find some place to "start" then figure it out yourself.

What I have seen done, is to run the bike at a certain speed (let's say 1,000 for idle long enough to let mixture affect plugs. Then without changing RPM's at all, shut off electrics to kill engine. Then check plugs. See color. If too lean, replace/adjust jetting for that particular RPM range. Then do at a different range, like 3,000 RPM. Key is to run long enough to affect plug coloration, AND shut off engine electrically so that it does not run on its own at any other range. Check plugs for color - then, change/adjust jetting for THAT range. And keep doing until plugs show an acceptable color (light tan) for all ranges.

Remember, a jet can be drilled larger to get more fuel (carefully).

This all has to be repeated several times as jetting at one range does partially affect jetting in other range(s).

See if you can get a "selection" of jetting from a dealer who will let you return the ones you don't use, and pay for the ones you do!
 
AFR monitoring

Seems the proper jetting and details a secret on this topic? I know this is a deviant mod, but seems like there is more about how to find the right sizes for a stock motor (plug checking and stepping up jets) than other folks experiences. Has ANYONE actually put TM Mikunis on an R100/7? Rather than paying for a box of soon to be unused brass, I'd rather pay someone to just tell me the best setup for my new slides- Seeing as they did all of the work already they may as well be compensated for it.

Thanks for any help on this guys.

1977 R100/7
1968 Chevy C10 (currently my towtruck)

Seeing as how you have engaged in what you describe as a "deviant mod" lol, you might not be adverse to taking the reigns and measuring directly the afr's that are developing as you ride and your Mikunis are performing. Adding a wide band sensor/ gauge allows immediate read on the behaviour of the entire system, and each bike/ motor tends to have its own quirks and ultimate reaction to say one given jet size. Although this is a rather simple install on most bikes, it does involve some rudimentary wiring, and the addition of a sensor bung to the exhaust work which may/ may not draw approval depending on a persons particular level of "deviancy". However, there is no more accurate way to see the full picture and take a stab at gaining results that actually deliver your desired operation.
I utilized an Inovate WB system on my bike prior to the more aggressive modifications, and was impressed and shocked at the behaviour & readings of the original stock Bings. Apart from rather dark reading plugs and tail pipes that always seemed to have higher soot content than normal, the bike ran very nicely and I would have been hard pressed to change things. In fact accel was going horribly lean, and cruise went significantly rich (can provide some numbers although mute point as you're seeking Mikunis data).
I can provide some recomendations on affordable and robust WB kits if you wish, otherwise good luck on your procedures and outworking.
Lorne.
 
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I've always wondered why aftermarket carbs are better than the Bings. I liked the accelerator pumps on the Dellortos, but the Mikunis don't have that, right?
 
I've always wondered why aftermarket carbs are better than the Bings. I liked the accelerator pumps on the Dellortos, but the Mikunis don't have that, right?

Some of them do, and some of them don't. :D
 
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