VM30s vs Flat Slide vs PWK on small honda twins

1969Honda

Been Around the Block
First off, I am buy no means a carburetor guru or expert, I'm a diesel mechanic and have limited experience with carburetors and gasoline fuel injection, I understand the basics and have screwed around with a few motorcycle carbs over the years. I've have noticed though that over the past few years everyone seems to be in favor of ditching the stock CV carbs on their CB/CL350s in favor of the Mikuni VM30 kits. I also recall reading somewhere on DTT however that CrazyPJ and a few others have mentioned a modern 28mm would probably suffice to provide the same power if not a little better than the VM30s; so are the 28mm TM series of flat side Mikuni/Keihin PWK 28s not up to the task or am I totally missing something here?

I had a ZX-11 at one point and thought long and hard about dropping the big bucks for some Keihin FCRs and know that the ball bearing slides is part of the reason they are so responsive so would the same effect come from a similar small flat slide carb on the little Honda twins? Thanks in advance for any forthcoming criticism and help!
 
What's your goal? on a stock bike, cleaned and adjusted, the stock CV carbs are a marvel.

Most people switch because they can't tune the engine to short exhausts and cheapo pods. (Not everyone, but still).

Unless you are making some majosr mods to displacement and induction, the CV carbs actually work very well for most people. They are designed for good drivability.

The Mikunis are simpler, but it also means if you go WOT quickly, they bog.

Racers run WOT a lot, so they are looking for WOT performance. But sitting at a light in traffic at WOT is a little more difficult.

So if you are staying mostly stock, the CV carbs will serve you well...

Also, a lot of people believe the Vm's will increase their HP, but the CB350/360 are already fairly highly tuned. The HP gain is usually at high RPM, with a loss of power at low.

Since you are a Diesel mechanic, what do you think is more powerful, a 400hp gas engine, or a 200hp deisel? (You need to tow 20000 lbs).

So number mean things, and often don't mean things. More HP at high RPM, is not always a faster bike....or a more rideable bike.
 
Thanks mydlyfkryzis! Bike is currently .75mm over bore, racing valve springs and lightened retainers, aggressive cam for more low end, mild P&P on exhaust, cleaned up casting marks on intake, cam similar to mega cycle x3 grind, no base gasket, copper head gasket. Mostly anticipated for some fun canyon carving in the local mountains and running back and forth to town about 20-30 minutes away. However it will be running a 160/60r18 SSSA once I get the alignment all figured out for the NT650 arm and vfr400 wheel that has been sitting half finished for 3-4 years now and the '98 R1 front end that's been on for 6 years.....

I strongly considering pulling the head off and having a bronze valve guides and some stainless valves put in just to ease my mind with the stock 40+ valves still in there with the higher lift and a little bit bigger displacement...
 
Better valves are good Honda used 2 piece welded valves. With a higher performance cam, one piece valves are better


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