Rerouting Vent Hose on KTM 250 XCF-W

I have a 2009 KTM 250 XCF-W and have the vent hose in the factory location running from the valve cover to the carb and was wondering about blocking off the carb and running the vent to another location. I have heard of this done on other models and would like some info on the plug for the carb and the proper location to run the vent hose.

The best solution is to use a longer vent hose and run it up the main frame towards the radiator then down and back to the stock carb connection. This way, any oil residue will drain back into the engine instead of the carb. There is no valid reason to the vent the breather to the atmosphere as this introduces the chance for dirt or water entrance.

P.S. To give credit, this is referred to as the 'CR500 Mod'.

Thanks for the sugestion on the rerouting of the breather hose. Do you know where to find that long of hose with the same inside diameter ? Why is it called a CR500 mod ?

I used a K&N looking filter on the end of mine and routed it to the air box.

Thanks for the suggestion on the rerouting of the breather hose. Do you know where to find that long of hose with the same inside diameter ? Why is it called a CR500 mod ?

'CR500power' had a post on 2/3/09 over at KTMTalk depicting the routing. Click on www.ktmtalk.com/index.php?showtopic=326650. He used a length of 3/8" fuel line, while I used some clear aprox 3/8" HD Tygon tubing.

Thanks for the help with the vent hose rerouting, I have 102 Hrs on my bike now and havent had any problems related to this that i am aware of but i have heard of oil pouring into the carb and dont want to encounter this.

only if the top end is worn out or the bike ends up upside down, that does happen of course:bonk:

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