YFZ450 Starter Idler Gear Compatible?

I've heard, but wanted to confirm that a YFZ(quad) starter idler gear assembly will fit a WR450. Visually, in a mediocre photo, they look similar. I have an '03 and want to change this out for a piece of mind... Any input would be greatly appreciated :excuseme:


That's interesting. The parts catalog says that the quad and motorcycle Damper Assys are the same part, with vastly different prices. Just hope that isn't a misprint. For info, the quad part# is 5TG-15560-00-00. Ignor the first 3 positions of the part# when attempting to compare part#'s for compatibility. Those 3 positions identify the model of vehicle that the part is used on.

Note however,that the motorcycle part# has been upgraded from 5TJ-15560-00-00 to 5TJ-15560-01-00. No way to know what was changed, however. I upgraded my 2003 to the 2004 configuration as soon as the 2004 models were available and never had a problem with the original configuration 2004 style Damper.

The price from Zanotti Motors for the quad Damper is $151.96 + $14.92 S/H. The price for the motorcycle Damper, part# 5TJ-15560-01-00 is $200.27 + some amount of S/H.

This is a reply that I made several years ago to an inquiry about the Starter upgrade. The prices are no doubt outdated, but the information should be useful :

Re: 2003 WR450 starter problem information for a potential new owner

Here is a list of parts, as well as a great price to upgrade the 2003 WR450F starter system to the 2004 configuration.

Look up <http://www.zanottimotor.com>

The price for the update to your starter system, if ordered through them, is less than $170 + shipping. Order the following parts from them:

5TJ-15560-00-00 - Washer - 1 @ $140.20 (This is the Idler Gear Assy/

Torque Limiter)

5TJ-1549B-00-00 - Torque Limiter Cover - 1 @ $19.80 (includes O-ring)

90201-105A8-00 - Thrust Washers - 2 @ $4.96

90380-10002-00 - Bushing - 1 @ $0.54

An alternative is to use this list and prices to negotiate with your local Yamaha dealer.

The fix takes 10 minutes. Look at page 4-78 in your 2003 WR450F Yamaha Owner's Service Manual for a visual on the parts involved. Take off the Idler Gear Cover and discard. Remove Idler Gear Assy and discard. Press the Bushing into the small hole in side case, where the Idler Gear was removed, with a hammer handle or similar soft object. Install one Thrust Washer on either side of new Idler Gear Assy. Insert new Idler Gear Assy in newly installed Bushing in side case. Install gasket (it's an Oring) from the old Idler Gear Cover or use new one on to the new Torque Limiter Cover. Install the Torque Limiter Cover using the old bolts. Done---go ride it.

Thanks for the info Baja... I did some research and found the number to be "close" but the price variable like you said. Well, I found someone who apparently has a couple of these YFZ idler gear assemblies. I've asked him if he could ship me one prior to paying to check fit. If this works out, I'll let all know. He's selling these for $59 + S/H. Not a bad deal, considering the options.

Good deal is an understatement!!!

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