Preparing for carb rebuild

[alpo]

Ultrasonic cleaning is the way to go. A good cleaner is a very modest investment and works exceptionally well with a solution of Simple Green and distilled water. About an hour in a heated bath and the parts come out looking brand new. Plus it doesn't harm o-rings and other sensitive parts.

[sledge]

Nah.......you should be forcing bits of wire through the jets, not bothering with the o-rings you can't see, forgetting all about the throttle spindle and choke plunger seals, not bothering with a sync' not checking for slide and needle/emulsion tube wear.

That's how we do it in here 

[user11235813]

LOL. I take mine to the local vicar who performs a carburettor exorcism.

Nah.......you should be forcing bits of wire through the jets, not bothering with the o-rings you can't see, forgetting all about the throttle spindle and choke plunger seals, not bothering with a sync' not checking for slide and needle/emulsion tube wear.

That's how we do it in here 

[Toner]

I no longer bother overhauling carbs myself.

I send them to a specialist who completely strips and inspects them before cleaning them ultrasonicaly and rebuilding them with the required seals and gaskets. He is an ex professional race bike tech, is very very good at what he does and has an excellent reputation in the circles and can do a far better job than me.

He did a pair of 24 year old GS5 carbs for me a couple of months ago, £85, yes......£85!
They came back looking and performing like they did when they left the factory and parts that NEVER get mentioned in the write ups you read in here were inspected, example fuel inlet barbs, choke plunger seals and throttle shaft seals.

For that money it's not worth getting your hands dirty.

Ask for Matt.

http://m.harpers-ultrasonic.com

Well I got a quote of him today. The £70 is decent but then the other parts can cost an extra £140 if they need replacing on his judgement. Did he charge you for seals?
His email:

A pair of carbs like yours will cost £70.00 plus parts and postage to clean.

As a minimum, a set of seals will add up to £40.00, but the parts spend can climb dramatically if there is wear present.

This design of carburettor can suffer from wear on the slide guide, needle and emulsion tube, these parts can add well in excess of £100.00, but are not always worn.

It seems that the wear can manifest from as little as 10,000 miles, but is more common on gently ridden bikes.

The first sign is a shiny patch on the front of the needle:- with the carbs off, open the throttle and lift the slide. It may require a spare set of hands.

Symptoms are normally experienced as a mid-range flat spot and off idle stumble.

[The Buddha]

If Buddha isn't able to find the parts, do you think this set will work if I request a 125 main jet and a 40 pilot jet?

https://www.discountbikespares.co.uk/ourshop/prod_5449514-CARBURETTOR-REPAIR-KIT-GS500-K-Y.html

You wont need 90% of these parts.
I've only seen O rings and the float needle "die".
You should be fine with just those, and having said that, I feel stupid - I didn't check if I had O rings Grrrrr. Anyway - I will have to do tomorrow, and if not, maybe early next week, cos I live in 2 cities now and could have them in either place.
Cool.
Buddha.

[sledge]

I was charged £85 for the pair. They have only done 11k miles but had been stood for 7 years.
I dropped the carbs off and picked them up myself, so no postage costs.
The 4 o-rings in each carb were replaced along with the bowl gaskets and the two fuel inlet pipe seals. (The ones either side of the T-piece). Matt is the UK agent for Litek and that's whose parts were used.
The slides and guides, the needles and emulsion tubes, the float valves and seats and the throttle spindle-seals were all inspected  and judged to be ok.
The carb settings were restored to factory setting, and balanced by eye.
I was told the tickover speed may be high on startup and it was.

I haven't actually tried the bike on the road yet but I can tell the difference just by the way it starts, hot and cold and by the smoother idle and cleaner pickup.

[Toner]

If Buddha isn't able to find the parts, do you think this set will work if I request a 125 main jet and a 40 pilot jet?

https://www.discountbikespares.co.uk/ourshop/prod_5449514-CARBURETTOR-REPAIR-KIT-GS500-K-Y.html

You wont need 90% of these parts.
I've only seen O rings and the float needle "die".
You should be fine with just those, and having said that, I feel stupid - I didn't check if I had O rings Grrrrr. Anyway - I will have to do tomorrow, and if not, maybe early next week, cos I live in 2 cities now and could have them in either place.
Cool.
Buddha.

No worries Buddha, I may just go with this service sledge is talking about to make sure it's done right.

[Toner]

I was charged £85 for the pair. They have only done 11k miles but had been stood for 7 years.
I dropped the carbs off and picked them up myself, so no postage costs.
The 4 o-rings in each carb were replaced along with the bowl gaskets and the two fuel inlet pipe seals. (The ones either side of the T-piece). Matt is the UK agent for Litek and that's whose parts were used.
The slides and guides, the needles and emulsion tubes, the float valves and seats and the throttle spindle-seals were all inspected  and judged to be ok.
The carb settings were restored to factory setting, and balanced by eye.
I was told the tickover speed may be high on startup and it was.

I haven't actually tried the bike on the road yet but I can tell the difference just by the way it starts, hot and cold and by the smoother idle and cleaner pickup.

So he only replaced 4 o-rings? 
Maybe that's why it only cost £85. 
Hope it's something similar for me.

[Toner]

Got it off and will send the carb out tomorrow for an ultrasonic clean. Thinking of replacing all the hoses will I'm at it.
Took them all off and taped them to some cardboard with the ends labelled.
There is one hose though that I cannot remember where it goes 

There are three connected to the carb, the vacuum, one that goes to the petcock and connects to a brown nozzle on the carb and a third that goes from a black nozzle on the carb to somewhere....
IIRC, it's the top hose and circled here. Not sure though because it's the straightest hose.
Can someone please tell me where it goes?

[alpo]

Where does it go? It's a breather hose. It goes to that canister, "FILTER, AIR CLEANER NO.2", which is a little filter. IIRC the older models simply vented to atmosphere. I'd have to lift my tank to verify.

[Toner]

Where does it go? It's a breather hose. It goes to that canister, "FILTER, AIR CLEANER NO.2", which is a little filter. IIRC the older models simply vented to atmosphere. I'd have to lift my tank to verify.

Must have the older one, don't see that canister. Hope I took enough pics to be able to re-install this 

[sledge]

Top hose is a vent, it tucks down behind the air box out of any draughts.

Bottom hose is the fuel supply.

3rd hose, the smaller diameter one is the vacuum pipe from the side of the carb to the back of the fuel tap.

[Toner]

Top hose is a vent, it tucks down behind the air box out of any draughts.

Bottom hose is the fuel supply.

3rd hose, the smaller diameter one is the vacuum pipe from the side of the carb to the back of the fuel tap.

Thanks Sledge, you think I can reuse the fuel hose protectors on these old hoses?
They're €8 each new. Old ones don't really slide off. Might be able to cut up the hose a bit to rip them off.