XS400 Maxim twin custom 2 into 1 manifold!

This was made by a member of thechopperundergound.com today. I drove down with my motor around 11AM and around 5-6 hours later it was done. I am gonna run a Keihin 36mm roundslide carb from a CR125 on it. More pics to come as it all goes together...manifold is made from 6061 alloy.

 

bump

 

it reminds me of my ex wife, big feet, sorry, it just does

 

bowlegged too?

 

NICE!!!
What about a 4 into 1 and run one carb for the XJ's????? Who's willing??? Just a thought.

 

OK I don't know much about the 400's what is the advantage here? Just to get rid of the rubber boots? Better flow of the air/fuel? Why not run twin carbs and maybe pickup some more performance? I know on the smaller cc snowmobiles there is a big difference in performance between the single carb and dual carb models? It does look like a quality peice and I hope it all works out the way you plan it.

 

the advantage is no more lame-o CV carbs. easier tuning, jetting, and throttle control/response. No more stupid diapragms. And since on a twin only one cylinder is being fed at a time, the single carb just simplifies things...

 

I like it! Good craftsmanship and I'll bet it runs just fine when you get the Keihin jetted for your bike.

Remember the old Brit bikes that offered single and dual carb versions of essentially the same bike? The dual carb version offered only a couple of horses in the RPM range that people rarely used if the dual carbs were synched. The duals did look 'cool' and I'll bet that's what sold buyers (like me, '69 Bonnie $640 out the door). :wink:

I'm betting that your setup works better. I like Tman's idea too. A nice aluminum manifold and a single larger CV would be interesting.

 

I like it too. You've actually hit on the solution to the whole carb tuning/rejetting for pods, etc., thing... GET RID OF THE !@#$%^&* CV CARBS! A twin running a properly made single carb setup runs fine as pointed out above.

Unfortunately a whole "bank" of Mikuni (or Keihin) slide-valve carbs is cost prohibitive for an XJ. Then again I often wonder if the $800-$1000 might not be worth it just to get rid of the blasted CV carbs...

 

here is the carb

 

I'd put a real air filter on it; you can get a "pod" or one of the "flat can" style with the opening around the circumference, like an old British bike.

Damn cool btw.

 

very nice, where are you going to start with the jets?
if it's any use i had a TT500 with a 34mm mikuni that used
210,220,240 main, depending on the year
air jet .8
pilot jet #35
the cut away on the slide was different than what i was used to seeing on a 2 stroke
hope that helps a little

 

not sure on jetting. From what I have read, it should start with what's in it. Then I'll go from there. I had to remove the hood that projects from the needle hole in the venturi area because it's not needed on a four stroke.

As far as a filter. I am gonna pass. I love the Vstack and TONS of harleys and old Brit bikes are and were ran the same way. It is gonna be protected where it lies anyways...

 

one other thing is as the head heats up it'll expand and put stress on the center weld, probably never be a problem, it looks plenty strong but if you were to use some RTV gasket stuff it might let it move a couple thou then there would be no stress

 

using custom paper gaskets and some permatex, thanks.

 

They've been running two two-into-one manifolds on Honda 750s for years that work great. I am thinking about trying some kind of setup on mine with a couple of two-into-one manifolds, but I still need to do some research on what kind/size of carbs I will need.
Maybe make the intakes 90 degress to the motor so I can mount the air cleaners out on each side of the bike and have them easier to get at! Just a thought. Could be opening up a can of worms too. Just a thought.

 

GOOD THOUGHT. It appears to be aluminum so its expansion rate should be about the same as the head. HOWEVER, if it were me, I would open the mounting holes up a bit so there would be a little room for "migration" without it binding up. Only if it fits TOO tightly should expansion be an issue.

 

yeah, it's aluminum...

 

mounted to motor...

 

Looks good. I hope it works out for you.

 

It looks great, and your valve covers are sharp too. I'm just wondering what kind of benefit it might have.

 

Can you make me a four-into-one manifold for my XJ so I can just mount the carb from an older Honda Accord on it? Why not?

 

Didn't I already cover that?

 

Yes you did. I didn't read page 1. Sorry. I understand now.

 

How did this work out for ya DW? need updates

 

excellent, except that the headgasket is leaking causing a lean surge and bubbling from the mating surface so I have to tear it all apart and re-do that. ridiculous!

 

dw- did i see your post awhile ago on the sagnasty CL asking for help tuning or something? someone had a 2-1 manifold and was asking for help..