Dual Carb, good or bad?

[harleyguy]

Hi Mike
The Mikuni 42 dual carb setup with 2 into 1 Rivera intake is a sweet looking setup. The big question is to how practicle this would be on either of my softails? One is TC 95 inch 10.5 comp, SE perf heads, SE257 cams. Other ride is TC 95 10.25 comp, stock heads, SE211 cams. My concern is will it be too much carberation even if jetting is played with. Will it work properly with either of my rides or am I just dreaming on this one. Most I have seen are on BIG inch bikes, although I saw one on a stock 883 sporty, believe it or not! Don't know if the bike even ran.
I have a chance at a new setup at a real deal and do love the look. I have to give him an answer on it in a couple of days so any help greatly appreciated.

Thanks

[Mike]

Generally it's more a cosmetic consideration than anything else. We achieve good performance with single carbs and simpler/easier tuning, it's all about the realestate available between the heads to make power. Different if we were talking true dual carb heads. Some of the earlier stuff did cause drivability issues, mostly stumbling with quick throttle changes but I believe the makers have resolved most of this with newer versions. The do look cool!!
Mike

[dynajohn]

I have a fortune invested in one of these dual 42 mic setups with a custom modified plenum manifold done by one of the best engine builders around. The end result was a setup that looks great but produces less HP & TQ than a big single carb setup. It was a good try but all I ended up with was a beautiful mantle piece mounted on a custom wood stand to remind me of how to waste money.

[Mike]

Another problem I forgot to mention is that, with forward facing setups, the runner lengths are not equal. Even though most are a plenum design this still affects the rear carb differently than the front. Second, air flow between the front and rear is entirely different because of the pathway differences to each port. Last, since typically only one of the two carbs has a working accelerator pump, idle mix screw and idle stop, tuning can be an issue.
Mike