Dynojet fitting - drilling out the slide lift hole.

[Dark Skies]

The instructions for the dynojet kit for my KZ1000 CSR reckon you should drill out the solitary slide lift hole out to 7/64" with the supplied drill bit.

I'm led to believe that this improves the throttle response. The thing is though ... I'm scared !!! If I make a hash of it then the search is on for a replacement slide (X 4 if I'm really clumsy). I'm also unsure as to how to secure the slide whilst drilling it out without damaging the external surface

I was wondering if anyone else here has drilled out the slide lift holes on a 1981 CSR / LTD / J whilst fitting a dynojet kit? Was making the leap of faith worth it?

Should I just fit the kit but leave out the drilling part? Is the improvement in response sufficiently noticeable to warrant opening it out?

[Pigford]

Dark Skies, I've done several Dynojet kits over the years and just got stuck in....

If ur a bit worried, just fit the kit without drilling the slide hole & see how it goes

If its no good, you'll have to do it

If you f**k it up, I'm sure an engineer can fis it, either sleeve the hole, or fill & re-drill

[Dark Skies]

How did you cope with holding the slides whilst drilling them? I have a pillar drill and a vice but can't see how you'd get a decent purchase with scoring the slide. I suppose I could put a tiny wood screw through the needle hole and screw it tight to a board and then drill the lift hole.

[Pigford]

From dim & distant memory, I think the drill only take a small amount of material off...... and as its soft zinc type casting, I wrapped some rag around the slides, then held gently in a vice and used a hand drill (old thing that you turn the handle to make it work)
Or a battery drill on slow speed would do

[Dark Skies]

From dim & distant memory, I think the drill only take a small amount of material off...... and as its soft zinc type casting, I wrapped some rag around the slides, then held gently in a vice and used a hand drill (old thing that you turn the handle to make it work)
Or a battery drill on slow speed would do

Seems it's somewhat academic now. I found one of the diaphragms was cracked. All the others were in acceptable nick though. A quick scan of my replacement options shows Wemoto's price for diaphragm kits is the cheapest and best option - a little over £57 buys you a diaphragm already fitted to a slide (or valve as Kawasaki has it in the manual) . I figure if I'm buying one I ought to just bite the bullet and get the other three too. That way they're all going to be starting off from scratch. The slide looks to be made out of some kind of plastic. It's likely that it's a little lighter than the Kawasaki metal version. So ... it kind of puts me in uncharted waters. Dynojet will have tested the pick up response on standard slides and come up with the 7/64" drill hole. But these pattern slides might be significantly lighter - which might quicken throttle response without the need to drill out the lift hole - or maybe not to the same degree at any rate.

I'm going to order a set. I have some uber sensitive scales that I use for reloading powders (I shoot rifles and load my own ammunition). If the pattern kits are a good bit lighter I'll refrain from drilling and see how throttle response is before making a decision

[Pigford]

Dark Skies, if you're considering coughing up over £200 just for slides, I'd think again mate...

You'd be much better off buying a decent set of carbs, eg:

33mm smoothies, or RS34's... etc

These will be much easier to tune and give more performance anyday

[Rich]

I assume you're talking CVs. I think the response is about how quickly the valve can move and works on pressure differences. The thing that regulates that is the hole that Dyno recommend enlarging to flow air through quicker and not the weight of the valve.

Please check this out as I don't do Cvs but I think you will find it is right.

[Dark Skies]

Lads,

If I were an ace tuner I reckon I'd plump for some sporty carbs and play about with them - and hopefully not damage my engine in the process. And back in the 80's when I could easily lay my hands on stuff I might damage I'd most likely go to town like I did with my H.

Unfortunately carbs have always been a dark art to me and parts aren't cheap and readily available for this bike anymore. So whilst I'd love to go adventurous with sporty carbs the smart part in my head says stick with what you know and try not to bugger anything up. Besides, a few owners back someone really did some work on these carbs. They've been heavily polished, totally kitted out with stainless Allen screws and they're really clean inside. The diaphragms look like they're the only old part in them. At some point the plastic blanking caps have been removed - saving me the bother too. So all I really have to do is fit the kit in ten minutes and bolt the carbs back on. Even Hammer-Fingers McSkies can handle that.

Anyway, if I bought another set of carbs I'd have shelled out £100 odd quid on the Dynokit for nought - and the full set of rebuild kits the last owner gave me would be wasted. And after spending the £200 odd quid I'd still need to buy another Dynokit and sort out a new throttle switch / grip arrangement (the CSR uses a single cable) etc. etc.

I know, I know. I'm a wuss. But let's keep it real - I just want a decent turn of speed. For insanity mode I've got the Speed Triple.


And I hear what you're saying on the vacuum differential side of things regarding the hole size. However, if a slide is lighter than standard then surely this reduces the amount of vacuum differential required to lift it? I freely admit I'd need to read up on CVs to even halfway get my head around them - but surely lighter means more responsive?

Anyhow - in wuss mode again. By trying the new slides without drilling them I can't do any harm. If it seems responsive enough - and let's face it all the junk I've pulled off the emissions side of things has got to help too - then I may just leave it as is.

If I'm fixing more than I break I'm happy.

[Dark Skies]

So everyone in the UK let me down on the slides front! A lot of spares sites listed the slides at around £57 / £58 a pop but when I bit the bullet and placed an order I was told they were out of stock and Tour Max (for they are the makers) don't know when they'll be getting some more out.

Fortunately there's a guy in America that sells a lot of parts for the older carbs and he's able to do slides fitted with diaphragms for around £37 a pop. Also has a lot of other stuff on his site that I've taken a shine to and I went a bit beserk with the old Paypal account. Orders over $55 are sent free of post (within the US). No sales taxes for foreign orders. Works out rather well for me as I'll be Stateside next Tuesday - so they're going to ship them to my inlaws for me to collect. Sometimes my plans actually come together!

Check them out here.

http://www.carbkitscapital.com