These twin carb kits have been around for a while, CycleX sells them for Honda750/4,s, they are usually used on chopper type builds with a central backbone, to give more room. I think the "performance" claims should be taken with a grain of salt, If twin carbs were better for performance you'd see them in race bike applications. CR's and RS carbs are performance carbs and can be had for similar money...
I know some people like his kits but i have never seen an apples to apples comparison or any dyno numbers to back up the claims. I'm sure they can be made to run well enough but one thing that you loose with them is the ability to balance individual cylinders.
I've got a set on my 1981. I almost have the bike back together and road worthy, I do have the carbs on and the bike idling.
The throttle response and tone is noticeably more aggressive. Makes sens as these are direct pull versus CV.
The manifolds will not fit flush in the stock boots. I took an end mill to mine so that I could fully seat the carbs. So far, no issues but taking it for a ride will tell.
Murray has informed me that this slight annoyance is getting fixed in a design update.
These things run RICH at idle and absolutely eat fuel when choked. I got a hold of Murray and he said this is normal.I did panic a little when I looked at the plugs and they were black as night.
The carbs come with a 2-1 throttle cable. I replaced them with a dual pull Domino throttle twister and it feels much better. However, Murray WAS NOT happy that I did this and recommends I do a vacuum sync. There aren't any vacuum ports available so I've added brass nipples to each of the manifolds so that I can sync them (as well as use the stock KZ petcock if I want to). I may just put the 2-1 cable back on just to try the bike but it did come about 10" too long.
On the first test when the bike got hot I did get a hanging idle that I could reset by blipping the throttle. It sounds like either sticking cables or leaky boots. I'm actively troubleshooting this issue.
All of this being said, Murray loves these carbs and is more than happy to help troubleshoot at almost any time of the day. I wouldn't exactly call these plug and play but they are pretty close and imo the direct pull Mukini's are far superior to the stock CV's.
Will post updates in the coming weeks when the bike is on the road.
I know nothing about these kits, other than reading about them and the pics on their web site. Will say with the intake manifolds they are changing the length from intake valve to air, which can work sort of like changing the length of primary pipes in exhausts. It can help to increase power at certain rpm locations.
I might throw a set up on Ebay here pretty soon if anyone is interested in giving it a try. I couldn't get em tuned up right, but I'm no mechanic either. In fact, I really shoulda known better than to mess with something like this.
The throttle does feel so much better though. My problem was the hanging revs. I went through it pretty good and the throttle seems fine and there are no vacuum leaks that I can track down. As far as I can tell, everything is installed correctly and the kit itself is in perfect condition.