Ninja EX500 carbs on an XS650?

Is there room to move the filters back by making extensions to carbs. See my post #1057 on page 53 of his thread.
By moving them back the filters and clamps may clear the necked section of the side cover.

This wont help with the carb clearance though, if it was my bike I would be tempted to trim the side cover.
My bike with side covers is a special and there were none of these issues thankfully.
 
Is there room to move the filters back by making extensions to carbs. See my post #1057 on page 53 of his thread.
By moving them back the filters and clamps may clear the necked section of the side cover.

This wont help with the carb clearance though, if it was my bike I would be tempted to trim the side cover.
My bike with side covers is a special and there were none of these issues thankfully.
Thanks, I don't think the filters are an issue actually. I've seen yours that you posted and it is a good idea.

The carbs on my bike seem to sit a mm or two closer to the rear of the bike than on others I've seen. Build tolerance. I'm guessing Yamaha had quite a wide allowance on that part of the frame fabrication. There's no real way round this other than trimming side covers. For that I'll be keeping a watch on eBay for a semi decent set.

Meantime I'll run it with the side panels missing.
 
It's remarkably easy to panel beat the the side cover front edges into the shape you want.
45 degree cable.jpg
 
It's remarkably easy to panel beat the the side cover front edges into the shape you want.
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Thanks. I'm not touching the originals. Unfortunately, it seems I missed buying a set of decent side panels just a few days ago at a very low price on eBay. I'll keep an eye out now for another fair priced set. Lots listed there but at silly prices and don't sell.
 
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Shake down of the back from the dead 650D is underway. Still not sure about the side panels not fitting with CVK34s. Keeping an eye out for decent used ones. But, I'm thinking that if I remove the gaskets between the inlet rubbers and the head, I can seal that joint with some good quality joint sealant. I like Loctite 574. There might just be enough room to fit the side panels unmodified as the carburettors with be mounted a bit closer to the cylinder head. Just something I'm considering for now. That's not happening imminently.

First couple of rides on the bike are very encouraging from a performance perspective. With the 2 into 1 Delkevic exhaust system fitted and the CVK34 carburettors, I think this is probably a unique situation. I'm mindful of not burning a hole in the pistons through a too lean mixture.

Yesterday's run was 5 miles. Combination of stop start, 50 - 60mph steady throttle and up and down gears. Then back home to look at plugs.

Very impressed with performance. The carburettors are clearly a decent option to replace the old Mikuni CV carbs.

Set up is 38 pilot jet, 2 turns on the mixture screws, JJJ needles in middle slot and 138 main jet. Foam filters.

Starting, throttle response, steady part throttle operation, closed thottle over run all pretty darn good. Plugs came out coffee coloured so I'm not running dangerously lean. I'll extend the distances I'm running over the next week or two, but it's an encouraging start. Plugs aren't this dark in daylight.

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Perhaps the last word from me on this thread. The carbs are working great. I have removed the gaskets from between the inlet port and the inlet rubber. The gaskets were 2.2mm thick. I fitted the rubbers to the head with Loctite 574 sealant which has a reasonable gap filling ability. The reason was to finally get my side panels to fit without altering them. Well, it's still really tight, but with the rear cross brace removed from the carbs and no gaskets, the side panels do fit. It's possible that with engine vibration, the leading edge if the side panels might still occasionally touch the carbs. But there's not much else I can do without being more radical. I just need to make sure there's no air leaks at the inlet port when I start up again.

Edited to add - Started up and runs fine. Inlet rubbers fitted without gaskets are fine.

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Linking my recently created thread to this one. No need to keep adding to it.
I got a set of CVK's last week. Ordered 80+ carb holders from JBM yesterday and jets/needles assortments from Ali Express tonight.
I have a set of VM's I bought about a year ago for my (soon to be) 79-SF retro-mod I have planned out in my mind. It's in my shed with the engine on the shelf in the garage, need to go through it again before getting it back into the frame which will need to be cleaned up & painted, along with the tank n bodywork.

Link to other thread: https://www.xs650.com/threads/bout-done-with-these-og-carbs.68990/#post-896023
 
Was wondering the reason why most everyone seems to be running the Uni 5229 filters.
I have a set of the XS Performance pleated filters that were installed by the PO.
Will they work with the CVK carbs or are there issues to deal with?
 
Was wondering the reason why most everyone seems to be running the Uni 5229 filters.
I have a set of the XS Performance pleated filters that were installed by the PO.
Will they work with the CVK carbs or are there issues to deal with?
Check the filters don't interfere with the passages at the carburetor inlet. For example the pilot and main jet air jets E and F on this cross section of a CVK carb. You may have to trim rubber away to ensure the ports aren't partially covered by filter rubber.

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thanks! i guess i'll order a idle screw refresh kit. my floats check out and i'm running the 40/140/#4 clip jjj (too rich, getting breakup on the crossover between the pilot and needle transition) but i can tune that out. carbs are definitely in sync, that was the first thing i did, i also am only running the pull cable and verified i have slack.

the idle screw itself looks good (not bent/dented/etc) wondering if i can just get away with this

http://www.cv-performance.com/cvp-mixture-screw-packing/

or if i should go with the easy adjust longer screws as well

http://www.cv-performance.com/ez-just-mixture-screw/
Do the o-rings in the Harley CVK carbs work? Mine are too hard and flat.
 
Ok. Parts are here. But not sure how all this fits together. Are there any pics to go by in this thread? How does the needle rise with the diaphragm?
 

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Hi, I am preparing to install a set of Gpz carbs to my XS. Nowhere in this thread has anyone mentioned replacing the needle jet. Does anyone know if the pwk28 needle jet will fit the cvk34? or do I fit the cvk34 needle jet & it'll work fine with the jjj needles.
 
Hi, I am preparing to install a set of Gpz carbs to my XS. Nowhere in this thread has anyone mentioned replacing the needle jet. Does anyone know if the pwk28 needle jet will fit the cvk34? or do I fit the cvk34 needle jet & it'll work fine with the jjj needles.
There's no need at all to change the needle jet found in the stock CVK34 carbs.

I put all my information in this thread from my fitting ER5 carbs and you'll see what I did and the jetting etc... as my posts progress.

Currently I'm very happy with the CVK34 carbs on my 650D.
 
There's no need at all to change the needle jet found in the stock CVK34 carbs.

I put all my information in this thread from my fitting ER5 carbs and you'll see what I did and the jetting etc... as my posts progress.

Currently I'm very happy with the CVK34 carbs on my 650D.
Cheer! I'm looking forward to slinging the BS38's. :)
 
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