Damn Yankees
Feb 18, 2002
My girlfriend’s little brother just got an old xr100 that has not been started in about 5 years. From the looks of it, it was not stored properly at all. Other that cleaning the carb and changing the oil, what else should I be doing before trying to turn it over and start it up? Thanks for any help.

David Trustrum

Jan 25, 2001
Ah!, it’s an xr100, she’ll be right. :aj: If it turns over & you’ve cleaned the carb & changed the oil turn the engine over with the spark plug laying on the head to see if it sparks. If so jam it back in & kick.

obviously new gas

If it’s a bit grumpy squirt a bit of engine start (or brake cleaner) down the inlet (pull the airfilter).


Apr 16, 2003
Do what the other guys said.Yes take the carb off and take it apart and clean/inspect jets and air passage ways,vents.The 100s went to CDI ignitons in 1990/91 so if yours is earlier there's pionts and a condenser.But don't worry about that yet.Make sure you got spark and fuel to the plug.


Dec 19, 2003
First, be sure the tank is clean and rust/sediment free. Then carefully remove the petcock, and clean the screen inside it. remove the tank to get good access to the top of the motor. Clean the area around the spark plug thoroughly.Pull the spark plug, and squirt some penetrating oil in there to help those bone-dry rings. With the plug still out, slowly rotate the motor with the kickstarter to get the rings lubed up. Replace with a fresh plug, change that old, acidic oil (it WILL etch the bearings, rings, etc. if ya start it with that old oil). Clean the carb THOUROUGHLY. This may be more involved than you think. Be sure to remove the jets, air bleeds, emulsion tubes, etc. Use a tip cleaner (for welding tips) to get the stubborn stuff out. Spray every single air and fuel hole there is and ensure they are clean. Be CERTAIN to service the airfilter. If a points ignition, new points and condensor. It also wont hurt to drain the old fork oil, and refill the fork tubes with fresh stuff. Finally, be sure to adjust the valves to factory specs, and set the timing chain tension to factory specs. xr100s required .020" cold, I&E. This is important if you want a smooth running, easy starting "one kick wonder". I have four old honda's. An '81 xr100, a '71 sl-70, a '70 ct-90, and a '69 mini trail 50. They all start on the first kick, and they are ALL on the original rings! Good luck.

Jon K.

Mar 26, 2001
Here's a trick for you;

Heat the carb jets (after you remove them :eek: ) with a propane torch till they glow slightly. That will turn all the goo to dust, that can easily be blown out.

Make sure you have brass jets, and don't use acetelene or MAPP gas, you will melt the jets away!! :flame:


Feb 5, 2004
take a look behind the ignition cover to make sure theres nothing clunking around in there, take off the flywheel and make sure theres no dirt or metal stuck to the magnets.


Feb 7, 2004
yeah, spray a LITTLE oil down the sparkplug hole, then if it's got compression, worry about getting spark first. You'll probably need to file the points with a points file or emery board, then run something like a clean rag or business card through the points to get any chunks out.

If you can get it running, but have a weak spark, then think about getting a new set of points and condenser. There's no reason to waste the money for new electrical parts if it's got a bad moter that'll cost more than the bike is worth to fix it.


Oct 23, 2003
everyone eles has good. idea. But i would also do a quick adjustment on the valves. if the valves are way out of whack you wont get a thing out of her.
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