Again with the zx9 float bowl mod thing

[whitelineweaver]

Well, after going to 4 different stores I've done it. The hose needed was about 14 mm but had to do with 5/8. The 13 mm retic T's a bit of a bodgy fit.

Also knocked up some speedo brackets out of a couple of mending plates from bunnings. Not sure if the position will work with the new headlight when that arrives. I'd like to use a single aluminium plate but not sure where to get. Maybe I'll bend them and paint black.
Attachment 4269 Attachment 4270

Waiting on a stator cover before I can test the bike.

[Dynomutt]

I've found the easiest way to sort out the float chamber pressure problem is to simply drill two holes in the underside of the airbox directly above the two Tee pieces for the float chamber vents on the carbs and then run a short length of hose from each Tee piece straight up into the airbox a couple of inches under the filter then slashcut the hose around 45 degrees and face the cut forwards. I've done this on several ZX9R that I've had on the dyno for setting up. It's much simpler than running bits of hose upto the front of the bike or putting holes in the filter.

[whitelineweaver]

Thanks for the info mate. I was originally going to do something like that (in fact I had your method bookmarked) but the way I went avoids drilling holes and putting filter over the hoses. If this doesn't work I'll probably try your method.

I'm going to put some carb screens over the intake holes which might reduce the air flow a little. I've got the impression that "ram air" only helps at speeds I don't intend going and that as long as I've got the same air pressure happening the bike will go alright.

Also, the bike has a K&N air filter with a chopped AM pipe. I asked the previous owner about it the other day - said he hadn't rejetted or anything. It seemed to go fine but I had nothing to compare it to. Hope it still goes fine after all this tampering.

[Redmohawk]

Once your all sorted , might be worth going to a dyno or decent bike shop and getting the tail sniffed to see where your mixtures are if it hasnt had a rejet etc. Most likely there are a few ponies hiding in the mix , or running a little lean.

[whitelineweaver]

I'll do that, cheers.

After reading up on it, it seems the popping sound on the decel isn't ideal. But it sounds good to me

[Redmohawk]

Popping is common enough with a opened up can, On decel only its prob lean. If its hunting at low revs (sits a little high then drops to normal idle or moves around a bit) also sign of lean.

[whitelineweaver]

Ah ha! The engine didn't sound steady at idle and I wondered if that was normal. Needed the choke on for quite a while to warm up too.

[Redmohawk]

Def lean then , I would get a tune asap

[whitelineweaver]

Will do, thanks man.
And I bought this off a mechanic

Think I'll start a new thread when my parts arrive. Hurry up stator cover!

[Hillsy]

They're jetted quite lean from the factory. Also the tubing around the fairings and into the airbox is more restrictive than when you run them naked so just taking the scoops off can make them run lean. Add in a K&N and a pipe and you'll definitely want a re-jet.

The rough idle might just be un-sync'd carbs though - makes quite a difference to have them sync'd.

[whitelineweaver]

Just spoke to a guy - $6-800 for dyno and rejet. Jesus! Just want the bike to run ok, not win a fucking race!

[Redmohawk]

Maybe have a chat with some of the boys in ASF up your way, I'm sure you could prob neg someone giving you a hand to sort it. Prob cost you a serious bashing of your beer fridge though.

[whitelineweaver]

Yeah that's a good idea. Maybe I could do the rejetting myself. Maybe I'll regret that thought.

[BANDITROD]

jump into the WA section of the forum and ask for help mate im sure you will get it

[whitelineweaver]

Once I get the bike running again I'll do that. Thanks fellas.

[Gix11]

Try and see if one of the WA lads knows a good Dyno guy who will let you do your own jetting in between runs. That's what we did round here. Get yourself a good selection of jets around the area you think you'll need. Maybe get one run under the belt first to gauge how far you need to go.

[whitelineweaver]

I'll try that, thanks for the advice.

[Dynomutt]

Thanks for the info mate. I was originally going to do something like that (in fact I had your method bookmarked) but the way I went avoids drilling holes and putting filter over the hoses. If this doesn't work I'll probably try your method.

I'm going to put some carb screens over the intake holes which might reduce the air flow a little. I've got the impression that "ram air" only helps at speeds I don't intend going and that as long as I've got the same air pressure happening the bike will go alright.

Also, the bike has a K&N air filter with a chopped AM pipe. I asked the previous owner about it the other day - said he hadn't rejetted or anything. It seemed to go fine but I had nothing to compare it to. Hope it still goes fine after all this tampering.

You don't need to put any filters on the end of the two hoses if they are inside the airbox underneath the airfilter, as the air that enters the hoses and thereby the float chamber has to pass through the air filter in the first place. Leave the air intakes in the frame open without any gauze or mesh across them, the surface area of any gauze/mesh will hugely restrict the airflow into the airbox and thus into the engine. If all you have done is fit a K&N filter and an open can then just increase the mainjet by 1 to 2 sizes, so if you have 135 mainjets then fit some 137.5 or 140 mainjets, and lift the needle with a small washer no thicker than 1mm under the head of the needle. This should sort out the midrange and upper rev range without a DJ kit.

[whitelineweaver]

I thought your method was similar to the yank on youtube. If the hoses are under the air filter, aren't they getting the unfiltered air before it goes up through the filter?

I need to double check with the PO about the bike. I should probably pull out a spark plug and check it. Any idea on what's needed BTW?- 16mm, thin walled? Tube spanner?

I like the idea of just throwing in some bigger jets and washers and seeing how it goes. Could I do that and not have to touch anything else like float valves and mixture screws? Where to buy jets?

Pretty sick of googling man! Thanks

[Dynomutt]

The hoses come up in between the intakes, although they're technically below the height of the filter they are on the clean side. You don't need any filters on the end of the float chamber breather tubes, most bikes do not have them anyway. I run my flatslides open with velocity stacks and breather Tee pieces open and have done for years without issue. As for plug removal the ZX9R uses CR9E plugs which are the 10mm thread size, you'll need a 16mm plug spanner, either get yourself a Kawasaki articultated one that is in the bikes toolkit, or find a thinwalled version with the rubber insert to hold the plug, you can use a normal 16mm deep socket but you'll need a magnet to lift the plug from the plug well, the Kawasaki toolkit item is a good little tool and uses a 14mm spanner on the end to drive it, I have one that I keep in my small underseat toolkit along with a 14mm spanner.