Quick one about carbs

MarkGoy · Borekit Bruiser Joined: 26 Jan 2017 Karma :

Does this look right? (petrol feed inlet)

model : GZ125 , year 2003, <10'000 miles.

Snod Blatter · Crazy Courier Joined: 21 Nov 2014 Karma :

Hard to tell from just a pic, but it does kinda look like it has been jabbed/"cleaned" with something pointy. Has anyone been in there before? Were the float bowl screws mashed?

If you put the float needle into its hole, does it seal? You can blow on the inlet where the pipe would fit to see if it works.
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1994 CB250, 1984 CBX250RS-E, 1989 K100RS, 1995 TRX850, 2016 Z250SL

MarkGoy · Borekit Bruiser Joined: 26 Jan 2017 Karma :

No idea, im the 6th owner.

I've replaced the floats and needle so I don't know that either. I don't recall seeing anything out the ordinary with those.

I've made a video if you wouldn't mind looking, I don't think it does seal properly.

The carb leaks you see.

https://m.youtube.com/watch?v=wNoyJGIP4Dg

After 1:15

Kickstart · The Oracle Joined: 04 Feb 2002 Karma :

Hi

Often the needle comes with a new valve seat. In this case I suspect you need that bit as well

All the best

Katy
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Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

MarkGoy · Borekit Bruiser Joined: 26 Jan 2017 Karma :

Hi Katy,

Sorry to be thick but what is a needle seat normally made of?

I bought new needles for this carb and that's all I've got, does this model not have a seat? Do all carbs get seats?

jaffa90 · World Chat Champion Joined: 06 Apr 2016 Karma :

MarkGoy · Borekit Bruiser Joined: 26 Jan 2017 Karma :

Sorry, I'm inexperienced in this tiny bit.

Needle seat : that's the metal bit I'm asking about?

If so how do I replace it?

Just had a look on wemoto, don't seem to have that part?

Kickstart · The Oracle Joined: 04 Feb 2002 Karma :

Hi

The brown bit is the needle seat. Normally this is a brass insert, which can normally be removed. Not sure if that one can as I can't see anything to hold it in place ( which suggests it is an interference fit).

Do you have a parts list for the bike / carb?

Not sure on the exact model but on CMSNL it looks like the seat is supplied with a new needle. Part 14:-

https://www.cmsnl.com/suzuki-gz125c-2000-y-e01_model13790/partslist/FIG9.html#results

All the best

Katy
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Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

MarkGoy · Borekit Bruiser Joined: 26 Jan 2017 Karma :

Right, that metal bit where the needle sits is the needle seat, there are no missing parts.

Ok.

Parts list, I've seen it, don't know how to find right now..

jaffa90 · World Chat Champion Joined: 06 Apr 2016 Karma :

Usually if the needle valve has a rubber tip then the seat is metal, also if the needle valve is all metal then the seat is rubber.

Pete. · Super Spammer Joined: 22 Aug 2006 Karma :

It's just a piece of brass with a hole in it, the cone of the needle seals in the hole. If the edge is damaged or burred then it won't seal.
Take it to an engineering shop and have them drill or ream it out a tiny bit. This will restore the sealing edge. If you were near me I would do it in a few minutes.

You'll need to re-set the float height afterwards but it'll be like new again.
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a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good Very Happy

MarkGoy · Borekit Bruiser Joined: 26 Jan 2017 Karma :

It's worth a shot before getting a new carb.

By re-set float levels do you mean to book settings, or changed to cope with a bigger inlet hole?

I'll take a look around, im close to Sheffield, im sure there's a few places about capable of it.

Pete. · Super Spammer Joined: 22 Aug 2006 Karma :

A bigger hole will raise the fuel level in the bowl. Mine you, so will a leaky float valve.
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a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good Very Happy

MarkGoy · Borekit Bruiser Joined: 26 Jan 2017 Karma :

Aah, right.

Would it not be better to get a new carb? If that thing can't be replaced and I have to muck about with the float levels?

chris-red · Have you considered a TDM? Joined: 21 Sep 2005 Karma :

MarkGoy · Borekit Bruiser Joined: 26 Jan 2017 Karma :

Is it literally just bending a tang? I don't have to change air/fuel or Jets or anything like that?

chris-red · Have you considered a TDM? Joined: 21 Sep 2005 Karma :

MarkGoy · Borekit Bruiser Joined: 26 Jan 2017 Karma :

alright cool, thanks Smile

Petemate · Trackday Trickster Joined: 13 Nov 2015 Karma :

Dunno about your carb OP, but mine has a seat which is pretty well impossible to remove, and is not shown on the parts list for my carb. Also the float in my carb is one piece plastic, with no adjustment of the float valve operating tang possible, unless one wants to experiment with a heat gun...
But then, my bike is after all 33 years old and I guess some younger machines are a bit more user-friendly!
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2008 Saab 9-3 1.9 Tid 150 Vector Sport estate
2005 Stirling Eccles Topaz 2-berth