Carb help

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Icecool
Posts: 8
Joined: Tue Mar 05, 2013 12:19 pm
My Bike: ZXR400

Carb help

Post by Icecool » Sun Feb 25, 2018 6:57 pm

Evening all,

After a bit of help guys, have bought a ZXR400 H-model 1989 (H1?) I've had a few issues with the bike, the coils weren't firing properly but after doing the stick mod from a guide on here and re-shimming it, she finally started. It is running a bit rough though, I do have two sets of carbs with it, one with heating circuit fitted and one without and from what I can see a few bits missing. The heating circuit carbs are fitted.

Few questions I have;

1. How do I know what model carbs I have, from what I read here the L-models had heating circuit but the H-models didn't which leads me to believe they aren't the standard carbs?

2. I can see on Fliece baythere are carb rebuild kits, seals and what not but does anyone have a recommendation on who to buy from? Don't want to buy a kit and then find it as poor quality 6 months down the line. (obviously dependant on what carbs I have)

3. Can anyone recommend somewhere to get the carbs professionally cleaned? It was laid up a good while and they were filthy, cleaned of most of the gunk but would like them properly cleaned before the rebuild.

Can see a few guides on setting the carbs up, one really well laid out one by Ross I think it was? But for an L model, assuming the settings wouldn't be far off if they are actually H-model carbs. Just want to get it running tidy first then planning on fitting a stainless manifold I got from coley and a micron can from the last ZXR I had and take it from there.

Sorry for the long post and thanks for the great guides and info you guys have here.

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banner001
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Joined: Sat Sep 24, 2011 3:27 pm
My Bike: ZXR400 L4
Location: Nuneaton

Re: Carb help

Post by banner001 » Mon Feb 26, 2018 12:48 am

1. You need to measure the inside diameter of the carbs, H model are 30mm, L are 32mm.

2. Litetek (http://litetek.co/) do the best carb seals for the bike, they are in viton instead of rubber and are excellent quality.

3. I can do jets for you, a mate of mine can do the carb bank if needed.
UK ZXR 400 L4
UK ZXR 400 L3 track bike
1989 FZR 1000 EXUP-R streetfighter

Icecool
Posts: 8
Joined: Tue Mar 05, 2013 12:19 pm
My Bike: ZXR400

Re: Carb help

Post by Icecool » Mon Feb 26, 2018 6:44 am

Thanks for the info Banner.

Will get them off after work now and measure them, tonight and order the seals. Is it ok to remove the heater circuit? Makes adjusting the idle mixure a porper PITA!

I'd very much like to take you up on that offer! They 100% need a good degunking. :gamer

On another note do you still do the starter lead kit? biggrin

Icecool
Posts: 8
Joined: Tue Mar 05, 2013 12:19 pm
My Bike: ZXR400

Re: Carb help

Post by Icecool » Mon Feb 26, 2018 6:46 pm

I can confirm that one set of carbs are 30mm and one 32mm. The 32mm being the ones fitted.

I'm assuming that it's better to have the 32mm carbs, better air flow from the larger aperture? Which leads to the question of do I need to put the jets from the H model carbs into the L model carbs to get it to run properly?

Given that the engine capacity is the same I'd imagine it will run just fine as they are. Also looks like someone tried to seal the intake collar to the head with some kind of sealant but it melted and run part the way down the inlet tract confuddled currently soaking the rubbers and collars in warm soapy water to clean them off and look for damage.

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banner001
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My Bike: ZXR400 L4
Location: Nuneaton

Re: Carb help

Post by banner001 » Mon Feb 26, 2018 7:33 pm

The 30mm give a bit better midrange compared to the 32mm carbs...the 32mm carbs give a bit better top end compared to the 30mm. I would jet the carbs to the manual, adjusted for your own fuelling/airbox/exhaust needs.

I'm still doing the battery leads, I'll get one cut for you, PM to follow soon, I'll also drop in it the contact details for my mate with the sonnicator bath, and an address for you to send your jets too.
UK ZXR 400 L4
UK ZXR 400 L3 track bike
1989 FZR 1000 EXUP-R streetfighter

Icecool
Posts: 8
Joined: Tue Mar 05, 2013 12:19 pm
My Bike: ZXR400

Re: Carb help

Post by Icecool » Mon Feb 26, 2018 8:39 pm

You're a gent banner. Much appreciated. The entire loom looks like it could do with replacing in all honesty but everything seems to work so your leads will be a good start.

Hmmm may get one set rebuilt and running tidy and rebuild the second set in the future then see what each set feels like I guess. Have ordered a full set of those viton seals too biggrin

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