Crass

The needle washers have arrived and I've posted up the dimensions in the sticky thread devoted to that subject. I got these NOS from Legend Motorcycles on the internet. They seem to specialise in buying up NOS, it's good prices and there's currently a lot of Suzook stuff that may interest members. 10% discount until 31 Jan with site10. They're not an OSS trader so I'll leave it at that.

So as I said in my carb rebuild thread I would measure a brand new set of OEM plastic washers, I thought a better place to post the info was in this related sticky thread. The diameter of the washer is 8.7mm, it is 2.5mm thick and the centre hole (not as easy to measure) is ~3mm in diameter.

I did look at the parts fiches but the Suzuki ones don't show these o-rings in the breakdown so there's no part number reference to go on. How did you order them - assuming the Bandit fiches also don't give that level of detail, or do they? Edit - got the OEM part number from that Litetek link and yes they come up as available from Suzuki at a reasonable price. For future reference the part number is 13278-47090 . That seems to be the old part number superceded by 13278-47091.

Thanks, I'll check this out.

Does anyone have a source for the o-ring which fits at the base of the slide guide and seals it to the emulsion tube orifice in the carb body. None of the seal kits seem to include it. Or is it just a case of measuring the old one and sourcing a generic viton replacement?

And finally I was reading the thread from some years ago about the plastic ring which fits on the needles and tends to wear. I see the modded versions are no longer available but the info was still useful. Mine seem to be a variety of thicknesses so have obviously worn, another issue affecting the fuelling no doubt. No point sticking those back in so I've sourced a set of NOS ones at half the price. When they arrive I will take accurate measurements and post them here so we all have a reference point in future as to what unworn ones should be.

This is the pre-rebuild dyno run from a few years ago. I'm hoping after all this work I can get a better result. Not absolutely awful fueling but far from ideal either.

After stripping down I dropped them off at Doncaster Motorcycles for a session in their ultrasonic bath. And the result -

And after given a good scrub.

I know you like pictures so here are some of the carbs as they came off the bike. They were filthy. The bike as it came to me seemed to have been sprayed up with a sticky preservative oil film. It had done its job but it was a right mess to clean off and as I never had the carbs off the bike I couldn't get those properly clean in situ. First job on removal was to get them degreased and scrubbed with a small bottle brush. Two bowls of filthy water later they were fit to be worked on.

Well I have to say I can't fault the customer service from Dynojet. Called them last week concerning the worn needles which I needed to replace and the lady on the phone was super helpful. Explained they don't sell needles separately but exchange them on receipt of old ones free of charge under lifetime warranty, which is what I was expecting from posts here. I also ordered new emulsion tubes and the 124 jets the Stage 1 instructions suggest should have been fitted. Sent my needles in and got a call this morning confirming receipt and that they will be exchanged and paid for the rest of my order so it can all be sent out. I'm not even the original purchaser of the Dynojet kit fitted. Outstanding. Slide guides are worn out by reference to the wear indicators so ordered a set of new ones from NRP, along with a pilot fuel screw which has seen better days having needed some persuading to leave home. I'll give the Wemoto gasket kits a try, having never had any crap from them so I expect good quality. Also like to say how invaluable all the info has been on here so far through doing a search of old posts and getting guidance on what to be looking for when assessing what needs to be done when rebuilding these. Thanks to everyone who takes time to share their knowledge.

Wemoto seem to have a good reputation for carb parts so has anyone used their carburettor gasket and float bowl kit succesfully? There is a considerable saving over NRP, especially as x4 required, although TBF the NRP kit does come with float valve brass seat (not required, I just need to replace the o-ring on the existing one). However, I don't want to buy cheap and pay twice if the quality isn't there with the Wemoto product.

Got everything stripped this morning. The extreme wear on the needles is on the section which sits in the slide, not in the emulsion tube. The slide holes all seem round so it looks like the plastic has worn the needles and they now rattle about in the hole. There is wear on the needles near the top where they sit in the emulsion tube but not bad enough to be clearly visible. You can feel a lip, not all the way round, with a fingernail and it's just about visible. I guess as fueling is so precise that would be enough to affect it. Regarding the power jets, the air jet in the bellmouth is not plugged like I said above but the one in the floatbowl is. I did wonder about this some years ago when I noticed the linking hoses were missing and I plugged the open end of the connecting pipe stubs with a dab of silicone as I wondered whether this would allow unfiltered air to be pulled through these pipes- looks like I was right. As part of the rebuild I'll make a tidier job with some rubber caps. Checked the emulsion tubes by putting a drill bit inside. I can't see any ovality but I'm just going to get a new set for what it will cost and be sure. I'll ring DJ and see how I get on with exchanging the needles.

Thanks very much for your advice, much appreciated. There's a good chance that this DJ kit has been in the bike for quite some time, possibly before they started using Ti needles. I have my doubts that these are Ti as they are a bright, silver, shiny colour whereas Ti is usually a duller grey. The way the surface is pitted doesn't look right either. I'll do what you suggest with the emulsion tubes to see if I can see any ovality. There are no Mikuni marks on any jets and tubes, so it looks like it's all DJ. The power jet in the float bowl is a plug. You can't blow through the plastic hose connector on the outside, it's blocked. The jet in the bellmouth is also a plug. I only have the external hoses connecting the two on carb 1, the rest are missing and one of the plastic connectors on one of the float bowls is broken off too. I wasn't intending commissioning the power jet circuit so it's not an issue. I have a feeling that the wrong main jet has been put in and being too small they have compensated by raising the needle. The pilot fuel screw is 1 1/4 turns out rather than 2 1/2 as DJ recommend and my dyno run shows the pilot is still too rich, so I guess they've tried to further compensate with this. Result is the bike runs ok but not as it should. My plan will be to buy the correct 124 main jets, send the needles to DJ for exchange, then set everything up as recommended and go from there. I'll strip everything tomorrow and list what I need.

I shall pack in for today after this and await any comments from knowledgeable OSS peeps before stumbling blindly on. So, main jets removed and I assume they are DJ as the only marking is a number 120. Again this doesn't exactly tally with the DJ instructions which recommended 124 with an aftermarket exhaust and can. The emulsion tubes look fine. Would I be correct in assuming that if they are not visibly worn / oval they are probably not significantly worn? Presumably they are DJ tubes. I don't seem to be able to get the emulsion tubes out of the plastic slide mount thingy by gentle tapping and as plastic is involved I'm reluctant to go nuclear. This may be academic as if the tubes are fine I'll leave well alone.