GS500F carbs on GS450, Done.

[Billy T.]

This definitely works, pretty simple bolt-on deal. I am running the standard 500f jets right now, and the bike is real close. Might need to shim/change the needle as there is a small flat spot in the middle, but for just cleaning them up and throwing them on, they work pretty damn well. I have pod filters and a 2-1 exhaust on my bike. Jets are 17.5/60/130. wait... I guess the mid main jet might be the one that is wrong... guess that makes a little sense, doesn't it

I am running the 500F cable, but I don't see why the standard 450 cable wouldn't work. Still haven't hooked up the choke yet and my bike didn't come with any of those parts either, but I won't need to worry about the choke for another 6 months down here. I'd be willing to bet the std choke cable would go on without much fuss, though.

The best part about this is that I only have 111 bucks into them. My bike didn't come with any carbs when I got it, so this was the perfect deal for me.

Anyway, just thought some of you guys might like to know. I have seen it mentioned before, but never really saw an definitive results. I'll post back as I get them dialed in a little bit better and what it took to make it happen.

 

[Guest]

Thanks for the heads up Billy

Good to know for the future so if anyone has a diaphragm die or something it may be cheaper to replace the carbs altogether.

What's the choke setup like on the 500 carbs? The 450 has a lever on the left side which I hate and will be impossible to use with my scrambler exhaust, so I've made up an adaptor to use a later model GSX600 left control module which includes a choke lever, and I've just reused the stock 450E throttle cable to actuate it.

 

[Billy T.]

It's a cable setup. Did any of the 450 and down bikes run a cable choke or were they all the lever type? I'd rather have a lever on mine, and was hoping those parts were in the bucket of parts I had, but no luck. Switching to the cable type might be just what you need Pete.

Also, put a few more miles on the bike today. Top end is a little further out than I had originally thought. Guess once it got some heat in it... but that would mean it was too rich. I need to go look at the plugs... It didn't buck and pop like it was lean, it bogged and stumbled. It wasn't bad, but noticeable for sure.

 

[davidduarte]

It's a cable setup. Did any of the 450 and down bikes run a cable choke or were they all the lever type? I'd rather have a lever on mine, and was hoping those parts were in the bucket of parts I had, but no luck. Switching to the cable type might be just what you need Pete.

Also, put a few more miles on the bike today. Top end is a little further out than I had originally thought. Guess once it got some heat in it... but that would mean it was too rich. I need to go look at the plugs... It didn't buck and pop like it was lean, it bogged and stumbled. It wasn't bad, but noticeable for sure.

AFAIK, the 450, 425, and the 400 all had a choke lever on the left side. The 250 had a push/pull lever. Not sure about the 300.

 

[Guest]

If you have a look in my rebuild thread, somewhere between posts 777 and 791 you'll sort of see what I did to make up an adaptor for the GSX 'bar mounted choke lever. With my forum settings, it's pages 78 through 80.

This is the left control module I scored off eBay for it:



Edit: Forgot to mention I've done more refinements, but without the bike here and not being able to cure the caliper paint with heat yet means it's not back together yet. Once I get the caliper paint heat cured in the BBQ the carbs can go back together with the adaptor and it should be good to go.

 

[Billy T.]

Plugs were lean. Put some restrictors in the filters and the hesitation cleared up.

Ordering 135 and 140 mains. Will post the results.

 

[davidduarte]

did the 450 carb to head and airbox to carb boots work bolt on, or did you have to make modification to anything?

 

[Billy T.]

No airbox on my bike. BUT, the inlets to the 500 carbs are bigger than the 450 carb inlets, so it prolly won't work with an airbox. The outlets of the carbs were a perfect fit for the 450 intake boots, though. Slid right in.

 

[Billy T.]

Put 140 mains in. Pulls hard and smooth all the way through the rev range. :dancing: Everything else is left as they were delivered.

 

[Guest]

Put 140 mains in. Pulls hard and smooth all the way through the rev range. :dancing: Everything else is left as they were delivered.

Thanks for the heads up Billy!

What did you end up doing intake side? K&N pods? Something different?

 

[Billy T.]

I had some generic pods left over from another build. They aren't Emgo, though. It's been such a long time, I don't remember what brand they are, but they have a W on the tip of them.

 

[Guest]

Cool, at least we know a starting point if we ever need to go down that path

 

[herostar]

Put 140 mains in. Pulls hard and smooth all the way through the rev range. :dancing: Everything else is left as they were delivered.

Did you take the restrictors out of the filters or leave them in?