Simplifying shroud installation on an '06-'09 with an IMS tank

5 replies to this topic
  • grayracer513

Posted December 30, 2010 - 04:26 PM


I won't argue that it seems odd that the aftermarket guys can't make a tank fit like the factory, but that's the way it is. Then, of course, some of us (we know who we are) have had one too many run-ins with gravity, and the radiators are not really bent, exactly, they just aren't the same shape they started out. Put all that together, and the once simple task of reinstalling the tank after routine service becomes a far bigger PITA than it should be.

The big problem seems to be the front shroud bolts that attach to the radiators. The factory design requires you to align the shroud with the bracket on the radiator, and then the threaded insert in the radiator louver with both of those while you screw a short little bolt into it without cross threading. Not so bad with completely straight, all stock setup, but not so easy with the IMS, especially with a slightly rumpled bike with a couple of hard seasons under its belt. Here's what I did to make it easier to deal with:

I first made two 38mm long studs from a pair of M6x1.0 machine screws, squared and chamfer the cut end, and cleaned the threads with a tap. I made them rather than buying them because that way the whole length of the stud is threaded. These I screwed into the radiator louver and ran them down until they bottomed, then backed them up a turn. Then I ran a washer and standard nut down on the stud and tightened the two:

Posted Image

Then I measured the thickness of everything that will be bolted onto this stud. This included a washer for the inside of the shroud, the flanged collar from the shroud, and a washer for the outside (arrows):

Posted Image

Next, I ran a cap nut, also called an "acorn nut" down until the cap nut bottomed, backed it off slightly, and checked that the space between the two nuts is smaller than the measurement of the parts stack that will go onto it. This assures the nut will clamp all the parts without bottoming:

Posted Image

IMS tanks like to have spacers installed between the radiator and shroud. The nut and washers are the spacing I used. You can add or remove as much as you'd like here:

Posted Image

Now, when you install the tank with the shrouds in place, you only have to pull the shroud down over a stud. The length of the stud needs to be long enough to engage at least 4 threads in the radiator louvers, but short enough that it won't let the top nut jam down on it:

Posted Image

Install the washer and cap nut, and you're done. Future tank R&R's will be far simpler.:

Posted Image

  • SXP

Posted December 30, 2010 - 04:35 PM



Where can you buy the cap nuts and what size wrench does it take?

  • grayracer513

Posted December 30, 2010 - 04:46 PM


I got all the hardware at Home Depot. The cap nut has a 10mm hex.

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • SteveO yz450

Posted December 30, 2010 - 06:30 PM


Sweet thanks Gray, I'll have to do this next time shes apart. :excuseme:
Steve O

  • cowboyona426

Posted January 04, 2011 - 08:18 AM


I'll be dipped... such a simple solution to such a HUGE headache. Thanks for sharing grayracer, I know what my next mod is!

  • SXP

Posted January 04, 2011 - 12:00 PM


The cap nut has a 10mm hex.

Thanks, it was what I was hoping to hear. I didn't want to have to carry an extra wrench/socket for some odd ball sized (possibly SAE) fastener for trail side repairs.

Related Content


Megabomb Fitment by 288yz450

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • 1 reply

The "going back to the other darkside" adventure... by Monk

Dirt Bike   Make / Model Specific   KTM   250/350/450/505 SX-F & XC-F (4-Strokes)
  • Hot  113 replies

Chubby dad, looking at bikes , First trip to the orange/black forum ! by Slow_ride

Dirt Bike   Make / Model Specific   KTM   250-530 EXC/MXC/SXC/XC-W/XCR-W (4-Strokes)
  • Hot  28 replies

Yamaha YZ450F 2017 by Chris.GVS

Yamaha YZ450F 2017
  • * * * * *
  • 1 review
  • Last review by Tommyk_55
  • On January 15, 2017

Is it worth it? (Cam and High compression piston) by macgi77

Dirt Bike   Make / Model Specific   Honda   CRF 150/230 F/L
  • Hot  36 replies

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.