Hello all,

I have just broken the 8000km mark, on my hopefully RTW trip aboard my Honda XR650L.

I have been extremely fortunate so far, and one of the few problems I have had, is carb related. I thought I would share it with you.

I have been keeping an eye on fuel consumption. A couple of times I noticed a drop in power, and significant drop in MPG.

Feeling that this was probably mix related, I stripped the carb, and felt that there was a bit of resistance to the movement of the `piston` in the `barrel` (sorry, probably not technical terms), especially when the piston neared the top of its travel.
I cleaned everything, WD40`d the diaphragm, piston and barrel, and put it all back together. Hey presto, fuel consumption better than ever.

I`ve done this on two occasions.
I always make a note of miles travelled between filling the tank, and hitting the first reserve. (I have a 22 litre Acerbis tank)
The fırst time I cleaned the carb, this figure jumped from 145 miles to 234
I just cleaned the carb again yesterday, and the figure went from 180 miles to 235!

Has anyone else had this problem?
Is there a longer term solution to the problem?
How do these figures compare to your fuel consumption?
What difference does the Edlebrook (sp?) carb make?

Just as a side note, I am extremely happy with the bike so far, and would not change it for anything. It`s extremely capable off road, quick enough on road, and always feels pretty planted.

Oddly, people always ask me how old it is. I often ask them to guess, and get replies of around 1991. They always laugh when I say 2008!
Hopefully this makes it a bit less attractive to theives.

Can't really offer any useful comment, but this might help with reassurance. I have a Honda XBR500, which has the same engine as your bike (the RFVC). I've owned it from new, it's now 23 years old with 80,000 miles. (130,000km).
I've never touched the engine, or carb, or anything else, and it's still the sweetest-running of all my bikes. Only ever did the usual servicing stuff, religiously sticking to the intervals (oil, filter, chains & sprockets etc). It's done a lot of miles all around Europe.
I thought the engine was so good I bought a Dominator (NX650). Secondhand. It too has done lots of miles, about 30,000 by me, and is completely untouched by me.
So you should have lots of faith in your bike's capabilities.

Maybe you are riding in dusty and dirty places around the world, so maybe the carb slide is getting dirty. Is your air filter good and effective?
On a bike I had in the 1960s, the carb slide would stick open sometimes (no throttle-closer cable in those days). The standard cure was to examine the slide to see if there are particularly shiny or scratched places on it, which would indicate it's rubbing a little in the carb body. There were, so the fix was to use a VERY fine file and carefully file those shiny and scratched places a little, carefully wash away all the filings, and replace.
Whether you try that is up to you, but maybe you're in a place where you just have to clean the carb regularly.
Otherwise, my experience has been the less you interfere with your bike, the better.
Ride safe.

__________________
TTR250 - London to Cape Town

Thanks for that Crankpin.
I do hope that my bike`s of a similar pedigree. I`ve had a few other XR`s in the past, and they have always been pretty solid, never really had any problems with them.

I am riding in dusty conditions, but I can`t see how anything could get past the air filter. The filter was new for the start of the trip, but that was a few miles back. I`ll give it a clean when I`ve got access to solvents and filter oil.

I`m happy to spend an Hr every now and then cleaning the carb, if that`s the answer. I would be interested to see if anyone else has had this problem though.

In terms of bike interference, I`ll confess to taking this probably too far. We`ll see if it comes to haunt me.

Cheers
Gabe
www.GABE-RTW.co.uk