Jump to content

Stumped & Chasing My Tale

Recommended Posts

Hey guys,

Need some help with my 450X which has me scratching my head. When under 175 degrees my 450X runs great. Once it starts going above 175 the bike starts popping, backfires, feels like it's being starved of fuel then dies. The electric start just cranks and it will only fire back up with the kick starter. Idle rises then falls until it stalls. Tokyo Mods just cleaned the carb, installed all new fuel lines, made sure the overflow tubes weren't clogged, and installed a new plug. I am at a loss besides thinking the ignition coil or stator are beginning to fail. 

What do you think?

Share this post


Link to post
Share on other sites

Do your fuel lines run near a heat source?  It sounds like when it gets hot the bike is leaning out.  If your fuel lines get too warm the fuel can vaporize in the line which starves the engine of fuel.  The popping, backfire, and rising idle and stall all sound like a lean condition.  I would start by checking where your new lines are run.

  • Like 1

Share this post


Link to post
Share on other sites

Thanks for the input. I replaced the lines with OEM part numbers although getting insulation for them is a great idea. I'll pick some up at a local auto parts store. 

Share this post


Link to post
Share on other sites
Thanks for the input. I replaced the lines with OEM part numbers although getting insulation for them is a great idea. I'll pick some up at a local auto parts store. 
hot start stuck?

Share this post


Link to post
Share on other sites
5 minutes ago, KEITH OLSON said:
On 1/27/2018 at 1:38 PM, BDTRENT said:
Thanks for the input. I replaced the lines with OEM part numbers although getting insulation for them is a great idea. I'll pick some up at a local auto parts store. 

hot start stuck?

I removed the level actuated hot start and installed the plunger type off a CRF/R to cleanup my handlebars and cables. I could have installed the new mechanism incorrectly. I will check when I get home. 

  • Like 1

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:


×