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View Full Version : Spacers between carb and intake



Patryn999
24th June 2007, 21:18
Hey just curious on my mate's motorbike which i've just got running again its got these hideous homemade spacers between the carburetor and the intake. If you know what I mean skip the next paragraph:

To give a little more detail you have the rubber sock that the carburetor slips into with a screw-clamp on the end but instead of the sock screwing onto the cylinder side the previous owner has placed a 1/2 inch thick rubber spacer between the face and the sock.

I was just wondering how this affects performance, say if I were to remove it?

The bike is a mess of parts - its a GSXR250 frame with a GF250(out of a GS250FW) engine with the carburetors off of a GSX250F.
euch.

Also as an aside could anyone give me a rough expected price range for a set of new jets (4 cylinder).

Cheers
Carl

merv
24th June 2007, 21:23
Longer intakes usually result in a milder engine response - shouldn't affect top end too much. Why the hell it was done to that engine I wouldn't know.

Removing them would be fine if they weren't meant to be there in the first place. How does the engine run now?

Patryn999
24th June 2007, 21:28
Its back to running ok now. Just ever so slightly lean and it has a spluttery flat response about half way through the rev-range but its got ok low down and ok high. (engine's not really a preformer :D)

Paul in NZ
24th June 2007, 21:37
the spacers usually insulate the carb from the heat of the engine as well and providing the correct inlet tact length.

Patryn999
24th June 2007, 21:39
To clarify the problem it feels like a hard stumble (splutter) about halfway through revs (cant really tell cause it doesn't have a tacho at the moment) which I would've thought was a richness problem but if you kill it and whack out the spark plugs they're faintly white which means lean. Tried raising needles which oddly enough helped the top-end but not much in the middle.

Patryn999
24th June 2007, 21:41
Cheers paul but could you clarify the "inlet tact length"?
Is there usually any indication of this in the service manuals cause i've got a couple floating around here.

Cheers

FROSTY
27th June 2007, 18:32
If Imreading ya right I suspect that the home made kit was so the bike would run. Given the motors from a different bike I wouldn't be suprised if the carbs are too.
Re the Jetting -again ONLY going by what you are saying I suspect the bikes got an issue runningup onto the Main jets.You might wanna try raising the needles a tadd either by puttingthemone clip lower or tiny nspacing washers--If that doesn't work then maybee ya could go up one size in main jets