Just finished my carb swap

[Vidrazor]

>>Vidrazor- I dont understand what you mean by the hoses getting super-cooled could you please explain a little more?<<

Well, I'm sure I have it all wrong, but I remember scuba diving once when we had a free-flow hose, rapidly dumping air out of the tank. Within minutes the first stage was coated in ice (in 90-degree summer weather) from the heat dissipation of the airflow supercooling. Had we not been able to stop it the first stage would probably have been locked frozen.

A similar continuous airflow occurs at the carbs, assisted by fluid flow no less from the gasoline vapor. Normally the carbs are up against the manifold, right? Here the air/fluid flow is passing rubber hoses. On a continuous run like highway driving, there's a constant flow of air/fluid going through there.

I suppose for whatever reason it's not an issue, but that's where I'm coming from with that question.

[Banditmax]

Vizrador theres very little pressure change in the carb situation meaning super cooling as your saying will not occur.

[Forde]

If your bike originally had the 33 mm carbs as my bike has why couldnt you just put the new ones on the old rack?  In fact why even swap them as they are the exact same carbs?  Unless your old ones were knackered.

[Banditmax]

Read the whole post buddy.

[camarobandito]

500 mile update-No issues whatsoever. Took it on a couple 80 mile trips with no problem. I did do some fine tuning and my mpg went up to 40-45 from previously 35. I did however leave the choke on a little too long and had a backfire through the intake. It shot the vacuum caps off like a rocket! That was enough to wake me up. Seems to be holding up well, only problem was that backfire and that was my fault. I will update again in another few hundred miles.

[doqq]

anymore updates?  i plan on doing this myself soon as well.  I just got the gsx600 carb . But I will probably go with factory pro kit, KN Ovals and add a slipon exhaust to it.  Thanks for the Inspiration! 

[Chris H]

Hi doqq,
I would'nt want to step on an idea but as Bandimax said the carb bodys are the same as standard and as camarobandito said he had an airline fracture in the stock carbs. From this you could take it that the reason the bike ran better than before is most probs due to the good set of carbs vers the bad old set. The longer inlet track may or maynot help low down and the wider set allow for easier fitment of cone filters but a known good stock set maybe better still, only back to back tests would prove this. If you would like to run cone type filters take alook at the link below.
http://www.400greybike.info/newforum/viewtopic.php?f=53&t=6892
The gk73 uses the same carbs as the B4 so this is a possible way to go.

[camarobandito]

Hello again everyone! Looks like the board woke up a little bit so I thought I would do a little update. Put about 2800 miles on it since the swap with only 1 small prob. I had a vacuum leak, wouldn't idle for anything. I took it apart and used a little JB weld around the pipes where the hoses slip on and all is well. Put 500 miles on since. Still not the prettiest but runs like a top!

As for the previous post by Chris H, I agree that some more testing needs to be done to see how much, if any gain has happened. The old carbs were not in that bad of shape, yes it had the crack but it wasnt leaking anything (yet) but would have gotten worse over time. As far as the condition of the old carbs, I was working on it that winter I accidentally left the petcock on prime and it never leaked a drop. It was like that for about 2 weeks until it warmed up outside. I notice just a small difference, I can break my back tire loose at 15 - 20 mph on dry pavement with little effort and I could not do that before.

Good luck with all of you that try it. It was a fun project to do so and much better (and cheaper) than trying to track down a couple new carb bodies or even a whole new rack. Low mileage gsx600 carbs are very plentiful b4 carbs are not.

I will post anything if it comes up, as for now I am declaring it a success. Thanks for the interest and let me know if there is anything I can help with.