Motorcycle Forum banner

1 - 5 of 5 Posts

·
Registered
Joined
·
10 Posts
Discussion Starter #1
Hi I've got a '74 Honda XL250 with super low mileage I picked up about 7 years ago. SO here's a brief history: thing's barely been ridden but not properly stored, bring it to my guy and he de-rusts the tank, puts new ignition switch on, new battery, etc. I ride it about a year then lose my keys... bike sits for year and a half, finally got a replacement key and it won't start. I get a new spark plug, drain/clean the carb, stick new gas in the tank and kick over until my foot is sprained... I can get it started but it idles very rough and won't stay started... It sounds like there may be a clog somewhere in the fuel lines, but I'm not an expert. Any way to troubleshoot and narrow down the problem? Thanks!
 

·
Registered
Joined
·
6,783 Posts
Fuel system cleaner is the simple answer...most likely the idle circuit jets will be clogged...esp if fuel with E10 was left in it. Get it running dump double the recommended dose in the fuel and allow it to flow through the carb then leave it overnight at least. Also with this being a 43 year old bike the fuel lines may need replacing...as will a lot of other rubber bits.

Good luck
 

·
Registered
Joined
·
10 Posts
Discussion Starter #3
That's a great idea, the only problem is I can't keep it running long enough for the fuel to circulate... it's like the lines are so clogged they can't deliver enough fuel to keep the engine running (I think). Is there anything else that would cause it to stall so quickly? Obviously I'd like to avoid changing the lines if they don't need to be changed...
 

·
Super Moderator
Joined
·
12,342 Posts
Chances are that it is running WAY lean so adding a little extra "choke" action might help it run long enough to warm up a bit and get some gas circulating.

If you put a double dose of a good cleaner in the gas, like Berrymans B12 Chemtool or Gumout, you can help speed the process some by sloshing it around in the tank to mix and then opening the drain on the carb float bowl so that fresh gas+cleaner can flow into the bowl. Then let that sit overnight and then try to start it.

The stock air box/filter needs to be in place. The choke needs to be full ON; that is the choke plate needs to be closed; verify the proper setting by looking down the throat if necessary. Then if necessary a little extra choke can be added temporarily by blocking off part of most of the air filter with something like Saran Wrap.

If it does start running better, then shut it OFF and let it sit overnight again before trying to ride it.
 

·
Registered
Joined
·
6,783 Posts
If you think the fuel lines are in such a poor state then you will be doing yourself and the carbs no favours putting off replacement. A simple test is to flex the various lines....any sign of hardness means they are likely allowing flecks of rubber to enter the tiny circuits of the carbs.

Also check the fuel filter...usually in the fuel valve or just inside the tank, typically on a 70's machine it will consist of a simple mesh screen directly above and fitted to the fuel valve assembly.

Check the tank venting system....easy to do... pop the tank cap open when it stalls if it runs fine afterwards then you have most likely found your problem.

Check the fuel line isn't kinked or trapped.

Getting back to the fuel lines this is a 34 year old bike the rubber lines will be fairly brittle by now I would think.

Good luck
 
1 - 5 of 5 Posts
Top