KLR 650 Ultimate Blue Subframe Upgrade


Drill bits not included. Image courtesy A.G.W.

You're riding along, doing things to your KLR that you shouldn't be doing... Suddenly, you hear a "THUNK," and it feels like your shock is blown. You stop and look, and see that your upper subframe bolts are broken, and the exhaust is holding up your seat. The stock subframe bolts support the subframe across the threads, which a) reduces the effective area of the bolt, and b) creates a stress concentration. While the stock grade 10.9 bolts have worked for many riders, and replacing those with grade 12.9 bolts has worked for many more (both have served the Big Cee Works KLR without failure), a customer requested that we go one better. The result is the Ultimate Blue subframe hardware kit. This kit replaces your upper M8 subframe bolts with a grade 12.9, M10 Metric Blue socket-head bolt. (Installation requires drilling through the subframe mounting crossbar on the main frame.) The bolt is long enough to place a solid, 10mm shank at both shear points. A stainless steel spacer and washer allow the use of a Stover deformed-metal locknut on the end of the bolt. The lower bolts are replaced with 12.9 Metric Blue socket-head bolts, with stainless steel washers included to give the proper bolt length. All Metric Blue hardware is plated to prevent corrosion. (My supplier has discontinued Grade 12.9 MetBlue hex head bolts, that were previously used in this kit. Socket heads will be supplied until I find another supplier or indefinitely if Metric Blue has stopped producing them. Apologies for any inconvenience.)

NOTE: If your upper subframe bolts have already broken, you will have to extract at least one of them (and preferably both) to install this kit.


You will need 5/16 and 13/32 drill bits to install this kit. The 13/32" bit may be replaced with a X, Y, Z or 10.5mm. The kit includes full instructions. You will need an 8mm hex key to install the main bolt (this size is not included with the standard KLR tool kit).

NOTE: These kits are designed to improve a potential weak spot in the subframe mounting system. They will not increase the load capacity of the KLR. Some owners who carry heavy loads have found cracks in the upper mount points on the frame. Be careful when loading your bike!

Part# ULTB1, Subframe hardware upgrade kit