2003 WR450F TPS Disconnect

I am fiddling with an 03 wr450f with stock pipe and 48pilot jet with plastic intake insert removed from directly under seat. I have been trying all sorts of pilot jets and turns on the screw. The bike just keeps stuttering. I read the threads about removing the TPS and blocking off the ACV. Anyways, I got frustrated with not being able to get rid of that annoying stutter and then unplugged the TPS. What a difference. My questions are these. First, is the TPS bad or did yamaha screw up bad? Second, when running these things wot on the straight trails in the upper penninsula am I risking engine damage due to altered timing? Is the default map better than the TPS can provide? These things are a pain in the butt. The flywheel already sheared the key as well so I lapped the flywheel back in and tightened the nut to 47ft/lbs as the dealer suggested. Help? :thumbsup::devil:

You need to plug an unplug the TPS for street riding and dirt riding(especially at low speed technical terrrain). Get the 04 starter upgrade for your bike the lap & loctite will not hold due to starter design issues. see www.wr450.com for info in the photo section. If you want a no tinker bike get an air cooled xr400. These bikes are not a pain in the A$$. You will not damage your bike running with or without the TPS sensor. I think the nut is 60 ft lbs. :thumbsup:

Thanks Indy,

I appreciate your input. The starter upgrade is my only reliable option? I'm not ready for a xr400 yet as I have to believe there are other non-tinker bikes in existence. This is actually a friend's bike and three of my other friends have them and have had no problem with there starters after the dealer fixed them last year in May. Just quessing, do you think the dealers did the upgrade last year and didn't share exactly what they did with my bud's bike so yamaha's reputation wouldn't get smeared? They told my buddies that they just lapped them back in and they have had 700 miles each with no problems. :thumbsup: I looked at the photo's for the upgrade. I am at work so forgive me if I am missing something, but don't you have to pull the flywheel and replace it to upgrade it. Or does the torque limiter do all the fixing? Go easy on me!

The flywheel doesn't get replaced. The only parts that get replaced are what you saw in the photos and Indy's write-up.

Only takes about 15 minutes to do the upgrade and parts can be had for around $200.

The write-up states a cost of $338 and nothing takes 15 minutes to do. It looks like it would take at least 17 minutes. :thumbsup: How many miles have you put on the bike since you upgraded? Thanks double d.

Dave is right if you buy the bushing and save the old side cover it does cost around $210.00 and takes only 10 minutes! :thumbsup:

Dont mess with Dave! :awww: He is the "Zen Master" around here! :devil:

Actually, I think Indy is the Zen-Master and I'm preparing to recieve an old-fashioned schoolin' from him when we hook up in Moab in two months. :awww:

Regarding the upgrade: It'll take 17 minutes if you're slow getting the aftermarket skid plate off. :lol: I was really quite suprised how quick it was. :thumbsup:

I sheared only one key before the upgrade and that was one year to the day I bought my WR at just over 2,600 miles! I have almost 4k miles on it now and still going strong. NO TSB completed, either. :devil:

Sounds good. I really appreciate the advice and the link. I'm sure we'll be talking again soon. Wish I had the time to go riding with you guys in Moab on my Husky 610. Have a good time out there!!!! :thumbsup:

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