Hey guys,

After a slight hiatus I have come back to the GS fold, what can I say a lightweight pocket rocket in the city is just too much fun in comparison to the tank of a Triumph Scrambler I have.

Anyway, this morning on my first true commute I was in town and as the bike heated up the idle got more and more difficult to hold, she passed out twice and I had to unceremoniously roll it off the road.

The bike has had the carbs rebuilt, but I noticed that above 80ish is just not possible and up to 4000 there is a little variance no matter whether I'm 2.5 or 3 turns out on the adjustment.

Plugs are the desired coffee and cream colour with no oil.

The only thing I am a little concerned is that a K&N replacement element is in there, but there has been no re-jetting etc .. although people say a replacement doesn't need it, my experience with cars is that they still change flow a lot.

Other than that the bike is stunning, 91 frame that has been totally overhauled, with a 96 engine with 19K on it, tank was POR-15'd etc etc ... basically a great wee bike for next to nothing.

Oh as a side note it does have an inline fuel filter, rather large and paper based, which seems to make the fuel line droop a bit too much, should the main feed have sag, or should it be at a near straightish path to the level of the petcock?

Any assistance would be great in diagnosing it, so I can get back to working on my nightmare of a 78 CB550


Steven

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If it's an automotive fuel filter, add a fuel pump or get rid of the filter...

yeah I've ordered one already, I was thinking it could be that, it just looks too big to be a bike based fuel filter.

Anything else I should check for outside of this?

Gas looks clean?  No corrosion in the tank at all?

Go to a home improvment store and buy a barb for now and dump that filter.

I bet thats it.

Gas lines clear? If so check them for bubbles while running on the sidestand or center stand. From what I have learned S(till new to these bikes ran off road previously), but the shorter the fuel lines the better.

Check float height on center stand with a clear 1/8 tube off the bowl drains.

Thats all 10 minute stuff that will get you a base point.

Gas is fully refurbished and has been treated with POR-15 so I'm ruling out rust.

I'll go and pickup a join piece today and some tubing to check the float level... anyone know what diameter tubing I will need for that?

Thanks for all the help so far guys, it's great to be back on such an active board.


Steven

1/4 OD works typically I think that would be 1/8 ID but I cant be positive.

Get a light in the tank if possible. You might be surprised with rust (although the filter if clear would show it hopefully) or maybe they partially clogged the internal filter with por-15.

It comes down to the application. If they had a bad tank and wanted to quickly do a por 15 job (if it is indeed por 15) and get it back up for sale they may not have taken as much care to make sure its done right.


I moved about 5-7 bikes last summer alone and I cannot even begin to tell you the crazy stuff I found done to them. A lot of people just dont care, especially if they are about to sell something.

Not trying to be the pessimist here, its probably ok and just that filter. But my lesson learned is dont assume they did what they said they did, or did it properly.

I do have my doubts about it, the worst I have had so far is the CB where I assumed the oil was valve seals, halfway into a top end rebuild it became apparent the owner had A: torqued the head on 3 times too tight and B: cracked every valve guide on the head ... not great at all.

Anyway, I've attached a picture of the filter, also you can see the sag in the fuel line, I'm thinking this could also be an issue as the fuel will evaporate as the pipe is too close to the block.



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K&N replacement? As in a drop in replacement? If it has the restrictor fitted then you shouldn't need to rejet.
Remove the in-line filter, there's no need for it. There is a filter built into the petcock assembly in the base of the tank.

Your line is definitely hanging too low there. I'm surprised it's not boiling fuel off and vapor locking the bike.

I'll take a couple of inches out of it tonight and see how I go. I thought that this morning that it's too low.

Personally, I'd just remove the filter and put in a straight barb. That should raise the fuel line enough.

finding a barb will be harder, plus I have a new filter on the way which is a proper inline motorcycle one.

I say ditch the filter and replace the line most problems with these engines are because of starvation if anything it rules it out...my tank had rust so i got what i could out and when the time comes ill clean the carbs again if youve done it once it takes 30min the second time around

Sent from my SCH-I535 using Tapatalk 2

Quote from: Suzuki Stevo on April 30, 2013, 05:50:42 AMget rid of the filter

Quote from: Snake2715 on April 30, 2013, 06:26:58 AMdump that filter

Quote from: mitch79 on April 30, 2013, 07:57:36 AMRemove the in-line filter, there's no need for it.

Quote from: Badot on April 30, 2013, 08:52:17 AMremove the filter

Quote from: NjDan on April 30, 2013, 10:05:20 AMditch the filter

Take the hint, man. That doesn't mean replace the filter with another filter, it means get rid of the filter.

Some of these new motorcycle filters dont flow well. I have seen it as recently on my wifes 250cc quad.

Dump the filter, get a new 1/4 ID line (Dont do 5/16). Or barb it and cut a section off.

That will aleviate a lot of it I bet. Check the air filter for the restrictor as well.

So new fuel line in, I managed to untangle the the other lines that were all getting crushed by the clutch cable. No filter! Even when removing the old one there was no flow from the filter, so I think that has been the issue. Carbs are on 2.5 turns out and the K&N will be getting removed as the restrictor plate is missing, which would explain the anemic acceleration above 60Mph. Lets see what some commuting and normal day to day driving shows up.

All in all I think the project here will be getting a bike back to stock, to then build on rather than building on top of an ill informed mess.

Biggest excitement just now is a new seat though, so no more slipping as I hand off nailing it round a corner! A beautiful hand sewn leather covered thing for £30!