That is the way I am leaning towards. there is some much information online it can get a little overwhelming.

 

A bit late as the OP has gone with the Mik but just an FYI, the below comparison test between a CV40 and a Mik 42 should answer any questions one might have about any difference in performance between the two. I will go with the CV any day, particularly on a touring model. Drill the vacuum port, install the lighter spring and almost eliminate the initial throttle response; not instant like the Mik with a cable actuated throttle but pretty dang close. As one would expect, the Mik 42 being a bit larger bore should have a bit of an advantage but the advantage is marginal. The CV is much easier to tune IMHO.

 

That has been my consensus too.
If I change carbs again I will just get a bigger version of the CV

 

SE CV44s are still around but the CV51,not so much; I have been looking for one for months. Only other CV option are the Woods modified CVs. Interestingly enough, Mr. Woods chose the CV to modify for performance, not the Mik.

 

.When I get this back together, if I feel it is lacking air up at the top, I will be talking to a couple different people that bore out the standard CV.
I have an HSR here and have tried it.
Truly It was not impressed.
With a couple cheap mods the CV comes off the line as well as any other carb.
Ports, carb bore, etc etc etc all play a part in the big word "volumetric efficiencies " that is the total VE of the engine.
Knowing what the total cube size of the engine gives a clue what power it will put out.
If it does not reach that we have to reason out why.
No magic, no mystery.

 

 

Well, as for the performance, I will let the data speak for itself. Not sure what you mean by "tuneability" but if you are referring to the ease of tuning, a CV is much easier to tune than a Mik. I will give the edge on throttle crispness and response to the Mik but, as I said in my previous, drill the vacuum port and lighten the slide spring on the CV and throttle response is pretty good. Never said the Mik was not a good carb but there is no way would I spend the $$ to replace a CV with a Mik which was the basis of the OP. Just not a cost effective way to spend the $$ which could be applied to a cam set, head work, more displacement, etc. which will truly improve performance while replacing the CV with a Mik will not as shown in the graph I attached to my previous shows.

 

this is nothing personal and NOT and attack, but that graph is only one example and not a true gauge to use. while the cv is good, for performance the mik is just better, it has more flow and more tuning circuits to work with. i would agree that for a stock or mild build the cost could be prohibitive, but for a strong performance build the mik is the way to go for me.
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