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Actual fuel level in carburettor? I can't find it, all the way down to page 10 on Google! !

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On my '95 xr600

If I connect a clear hose to the carb drain where should the fluid level sit? Is it exactly on the joint of the bowl and main body?

I know from my Haynes manual that the float top should be parallel with and 14mm from the jointing face of the carb. I'm concerned my float has begun to absorb some fuel...

Any help would be much appreciated.

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Thanks for bringing up that trick. Too bad they aren't externally adjustable.

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That would be a lot easier but it's not too difficult to hold the bowl in place and take off again in order to adjust in place, especially if your worried it is a dodgy float.

Any idea of the correct level?

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I've always set them when the carb is off. There are few people who would try and be as precise as you are and the information you seek is most likely buried deep or not available at all.

 

How about measuring the distance below the bowl interface on the carb body that the pilot and main jets are then you can determine how much the fuel level in the bowl is covering them.

 

I think you're doing something that everyone could benefit from the information you gather.

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I could measure my 97 xr6, but it feels like it may be a little high or rich. But IIRC it is not near the parting line. Another factor is, bike needs to be measured at same pitch every time. You want me to have my bike absolutly level? front to back & side to side? This would be the most repeatable for accuracy.

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I don't understand why you guys are trying to measure the float height this way.

 

Whenever I've measured the height of a float, I have the carburetor out of the bike, have the float bowl off, and hold it sideways so that the float is hanging down.  I then tilt it until the float just stops moving and measure the height from  the base (where the float bowl seals to) and use that value.

I can remember the first time I rejetted a Ducati Monster and the Factory Pro instructions recommended a float height that was 5mm lower than the stock setting.  That was such a big amount that I called Factory Pro to verify.  They actually answered their phone on a Saturday and reassured me that their value was correct.  The bike ran great after the change.

 

As for the float absorbing fuel, could you shake it and see if you feel anything inside?  Or weigh it and compare to one known to be good?

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I don't understand why you guys are trying to measure the float height this way.

 

Whenever I've measured the height of a float, I have the carburetor out of the bike, have the float bowl off, and hold it sideways so that the float is hanging down.  I then tilt it until the float just stops moving and measure the height from  the base (where the float bowl seals to) and use that value.

I can remember the first time I rejetted a Ducati Monster and the Factory Pro instructions recommended a float height that was 5mm lower than the stock setting.  That was such a big amount that I called Factory Pro to verify.  They actually answered their phone on a Saturday and reassured me that their value was correct.  The bike ran great after the change.

 

As for the float absorbing fuel, could you shake it and see if you feel anything inside?  Or weigh it and compare to one known to be good?

Scott, you are right, this is the correct way, but for quick reference, without taking carb out.

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Scott, you are right, this is the correct way, but for quick reference, without taking carb out.

Okay, I get that, but you can only do the quick reference part AFTER you've verified that everything is correct.

 

Personally, I think it would be worth more to have one of those quick reference oil tubes hooked up to the steering head.  I've read through instructions on how to add one to an XR650L, but nobody has mentioned it lately.

 

 

What we really need is quick reference for the carburetor, for the oil level, for the fuel tank, and for the brake fluid reservoirs? ;)

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.... and for the brake fluid reservoirs? ;)

I really hope you're joking about that part.

The OP is not talking about leaving the tube on the carb. The drain/overflow tube is replaced with a clear tube, the tube is open on the end and raised above the anticipated fuel level then the bowl drain is opened. The fuel level in the tube will be the same as in the bowl, providing the person reads the meniscus correctly.

Some automotive carbs have sight glasses and the FUEL LEVEL is set via externally adjustable floats. The goal is the exact same as bench setting a float; proper fuel level.

What the OP is doing is a good way to quickly check the fuel level, but if it is incorrect at least the bowl has to be removed because the is no external adjustment. Thus far, no one else has posted the data the OP asked for and I for one am looking foward to the results, it will be valuable information that I have'nt seen posted on here, ever.

Edited by Onederer

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The drain/overflow tube is replaced with a clear tube, the tube is open on the end and raised above the anticipated fuel level then the bowl drain is opened. The fuel level in the tube will be the same as in the bowl, providing the person reads the meniscus correctly.

Now I understand.  This sounds like a great way to check the level.

 

Too bad the XR650L doesn't have a drain tube.  It only has the overflow tube.

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The XRL tube is a drain and overflow tube- little screw sideways at the bottom of the bowl.

I just had an XRL float bowl in my hand a little over a week ago.  There was no opening out the bottom from the inside.  It comes from a cast tube at the top that only lets fuel out if there is too much in there.

 

I've had carburetors that had a big screw at the bottom that let you open them to get to the main jet, and I've had carburetors with a small screw at the bottom that would let you drain them out a tube connected to the bottom, but the one on the XR650L doesn't have either of those.

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Bork , if you could measure yours when you got a minute, that would be great. Then at least id know my float was a problem (sinking) if it was higher than yours. You don't even really need a clear tube as you can turn the drain tube and move it up and down until the fuel is exactly level with the top of it.

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Carburetor fiche for 2013 XR650L:

http://www.bikebandit.com/houseofmotorcycles/2013-honda-xr650l-carburetor/o/m154751sch794434

 

The drain valve is that numberless part that looks like a screw at the bottom of the float bowl.

So maybe that's a recent addition.  But it was not on the 1994, 1999, 2001, or 2005 XR650L carburetors that I've had apart.

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It is on my 2001 XR650L.

Now I"m going to have to remove the float bowl on my 2001 and photograph it.  Gee thanks. :foul:

 

 

Edit:

It might also be a California thing.  There are other things on the California models that are different from the rest of the country.

Edited by ScottRNelson

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To check the carb float, removing it and holding the part in your hand will make it pretty apparent if it has filled with gasoline.  I've also heard of testing its flotation by putting it in a small dish of fuel.

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