Ninja EX500 carbs on an XS650?

am running 40/140jets, stock needle, open pipes and Ramair(Uni-filter) pods...plugs looked rich, though not awful and running pretty nice....went to calculate MPG today after running through full tank, and am only getting 25ish! obv my daily commute through central London aint gonna get me best results, but thats pretty shocking...:eek: I have 38/138jets will try them and see what happens!
 
If you read all of this post submissions you would see JJJ , GJH, HKJ are the suggestions with the JJJ being the richest and HKJ the lean.

I'm running the GJH with 40/140 and will be switching to 38/138 and playing with clip position, currently set at #4 counting from the top down 1-5.

Hope this helps.
 
Demorgan,

Hello from a fellow Brit, mate. What Brian902 is alluding to are Keihin PWK 28 needles; 'PWK 28' being an aftermarket Keihin carb. This mod uses CVK jets and one of a range of PWK needles. A standard GPz500/ER500 CVK needle does not work, as you've found out. To use a PWK needle you have to carry out certain mods to the needle holder set up. Nothing drastic. Take some time out and check back for my and other's early messages to see how to do it. Obviously I prefer my way!!! Also, from what I've seen so far, once the motor is finally dialled in, not many people end up with a 140 main. I haven't. If your bike's set up is not that radical a 140 will only contribute to less than optimal mileage; correct needle selection is the key to this fine mod. Once again, look back in this thread to get an idea of the way forward for you.

If you need any assistance give me a shout. Good luck.
 
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oh yeah, i will try needle too, its on order! dont worry, i have read ALL the thread, was more just posting my results so far..

and thanks!
 
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My guy has figured he's getting about 42 mpg, so we are looking to lean out the mid range where he runs the most, thus the change to needle clip positions and may use a washer to get half steps.

Hey, I thought you Limeys where liters and kilometers / liters per 100 km and all that wonderful metric stuff.
 
We Canucks do that just to piss off ourselves and of course the Americans!!!

And I speak two languages, English and Cursing, just enough to confuse everyone further.

LOL!
 
Quick question, I have the ex500 carbs on my project tc bro hardtail bike right now working perfectly.

Im not going to be using the stock throttle housing but an aftermarket one such as, http://www.tcbroschoppers.com/7-8-throttle-assembly-with-vintage-style-grips.html.

My question is what should be done? Can I use the stock xs650 throttle cable? I believe it is way to long right now. Im going to be using drag bars. Im not sure what I have to order at this moment. This is the only thing I am really confused with on my build, any help would be appreciated.

Thanks.

Posted via Mobile
 
Hi

Is there anyone who knows where to find inlet manifolds in aluminium that will fit XS650 with EX500 carbs?

Thanks
/Mattias
 
Gmorrone1214 said:
Can I use the stock xs650 throttle cable? I believe it is way to long right now. Im going to be using drag bars. Im not sure what I have to order at this moment.
Click to expand...

Hi GM,

If you've already decided that the cable is too long then you've answered your own question and you're likely headed down the bespoke cable route as many have already done. However, I think you're wanting to know if the the XS650 cable has the correct nipple to fit the CVK carbs. It does. And, to answer another question you may be thinking of, you don't need a pull/push cable either; a single cable works fine.

But going back to overall length, are you aware that the standard 'roadster' cable is shorter than the cable fitted to 'Specials'? That said, if you decide to use either of these cables you're probably going to have to shorten the outer a little. I had to trim off about 3/8" to make it fit properly. It's very easy. Ease the ferrule off the outer, carefully cut off what is needed on the outer then refit the ferrule. If you look back you'll find my post in which I describe what to do. There's a pic too.

Hope that helps.
 
Hello 1800skold,
I know that the beautiful aluminium manifolds from 650 Central designed for 34mm VM carbs won't work. The two most obvious problems are lack of space between the cylinder head and the frame down tube and the spigot size of the GPZ/EX carb is different to the VM.
 
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1800skold said:
Hi

Is there anyone who knows where to find inlet manifolds in aluminium that will fit XS650 with EX500 carbs?

Thanks
/Mattias
Click to expand...

I use the TC Bros manifold, however I had to cut them down to make them fit, it's tight but they fit and work well

M
 
ok, have rejetted to 138/38's, JJJ needle on middle clip position... runs ok, but only really starts pulling hard at 3k and also doesnt like starting without choke at all, though once started idles fine between 1-1.2k. mix screws 2.5 turns out. straight through pipes and ram-air pods. reckon change clip position, down?

also, why feck are those extended mix screws ye can adjust by hand so bloody expensive?? 38quid for (i hope) a pair! even more from Truimph specific pages (as CVKS are on early Hinckley Bonnies).
 
Demorgan said:
ok, have rejetted to 138/38's, JJJ needle on middle clip position... runs ok, but only really starts pulling hard at 3k and also doesnt like starting without choke at all, though once started idles fine between 1-1.2k. mix screws 2.5 turns out. straight through pipes and ram-air pods. reckon change clip position, down?
Click to expand...

Hi DM,

Sounds like it's pretty good at the moment. If there are no noticeable flat spots or stumbling then I'd run it around like that for a while until you get used to it. Then you may start to pick up things that are not quite right. Don't forget to do some town riding where you'll be using only small throttle openings. But be aware that these bikes do suffer from a little transmission/chain snatch during town riding, something that is hard to avoid. And don't confuse snatch with a flat spot and try to cure it through jet and needle/clip changes......although a low rpm flat spot will increase the severity of transmission snatch! LOL!

I doubt if you'll get it to pull much harder below 3k if you're not already experiencing a small flat spot upon opening the throttle at low speed/small throttle opening. And bear in mind that moving the clip effects the mixture from off idle all the way to approx 7/8ths throttle so you may cure a problem lower down in the rev range only to cause a new problem higher up. You're then heading into into needle change territory.....

For now, keep it as it is, and ride it around for a while. Note any recurring problems then have a long, hard think about what you could do to cure them remembering that changing /altering one component has a knock-on effect on most of the others. Then decide your plan of action and let us know how you get on.

Good luck.

P.S. Just noticed your 'choke' comment. Are you saying that it always has to have choke to start no matter if it's hot or cold?
 
Cheers, Nomad! I live in London and commute across central everyday on it, so town riding is pretty much ALL i do! yeah, chain snatch is very annoying as very frequent with all the stop-start, 1st gear dawdling i must endure! have to say its not really the greatest bike for purpose, it particularly doesnt like sitting getting hot and bothered in traffic but any stretch of clear road its sheer joy!
Thats all very reassuring, i recently made a round trip of 200+ miles down to the south coast and round sussex country roads and 80mph+ motorway and didnt have any probs, so perhaps not much to be concerned about..!

oh, yes, and when warm, starts without choke but on starting in morning first thing always need choke even a warm day, but perhaps this isnt so bad. just used to modern bikes that dont require coaxing and stroking and nice words before coughing and spluttering into life early in the morning. like the rest of us!
 
Hey guys,
I find at my disposal a pair of 3D printers capable of doing Nylon parts. Kinda thinking about making some air filter to carburetor spacers to adapt the shorter EX500 carbs seamlessly. Would that be worth $30/pair?
Discussion starts below.

:p

Thanks!
E
 
So I had to install a whole new complete wiring harness cause on emergency mode (no fuse) I burned it up. I know, not recommended. How ever, got the new harness in and I'm leaking fuel from my fuel rail or rings, by the looks of it. Maybe it's because they've shrunk due to sitting without fuel for the summer, or perhaps it's just their time to go. Either way I'll need a few before I'm back on the road. Anybody got the part #s handy? It's been awhile since I've been here...

Otherwise I'll put in a word for mikesxs complete stock harness. Thing was completely plug and play, each wire was exactly as the original and required zero adjustment of fumbling with. For $60 you really can't miss with these. +1 for mikesxs!
 

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