Holy sprocket nut Batman!

BSKZ650 wrote:

...kind of ironic, the locking washer on mine died and the nut fell off while riding, was not fun at all

ummm, Riverroad, you DID flatten the locking washer down, didn't you? :lol:

You might try sticking a bar or pipe between the shocks and one of the spokes if you have a mag wheel, putting the bike into first and rolling it forward until the bar locks to keep the output shaft from moving while you lever against it. A 5/16" drill bit seems a liitle under what might be needed. The breaker bar should really be enough. . .

:laugh: Yes, I did flatten the washer.
Well yesterday I went by Harbor Freight to get me that impact wrench. They didn't have the one I wanted (above), and I ended up getting the lesser 250 ft/lb model. That was a waste. I stuck it on that nut, hit the reverse button and pulled the trigger. That nut just sat there and laughed at me. Oh well, it's true. Ya get what ya pay for.
So I did some cussing and rootin' around the garage and finally found my cheater pipe. Stuck a piece of 5/16" drill bit shank through the chain and let it wedge up against the block casting. Stuck the 1 1/16" socket and breaker bar with pipe on there and started pulling. Real hard! The breaker bar was bending so much it was popping chrome off of it.
Something gave with a very loud snap, and for a second there I really WAS worried I broke the output shaft, but when I looked, it was the nut that finally came loose.
Hallelujah!! Man! They really torque them suckers on there don't they! I hadn't run across a nut that tight since I worked in a naval shipyard!
So now, with the weather getting a little better, I should be able to clean up and paint the rear section of the frame and swingarm, put the chain and sprockets on and get it back on the road.
Thanks guys! Now I gotta go chase around all the "loose nuts" at work.:side:

Nut is a 20mm nut with 27mm outside size. The pitch is 1.5 I think. A NORMAL 20mm nut generally has a 30mm outside size so if you buy a replacement, it will likely be larger and require a 30mm socket. The main problem with most replacement nuts is that they will be too thick but Maryland Metrics does have a thin 20mm that will work fine. The only issue is the mechanical lock washer that goes under the nut and there isn't as much sticking out making it harder to bend over the edge but it can be done.

So, do you think I should use a new nut? I checked this one (and the shaft) over and it all looks good. No damaged threads that I can see. Smooth glide on the assembly.
I was planning on using it again, and just bending up a new section of the washer.

after the mess on the side of the road, and the washer was only like two bucks, I ordered a spare, any time I am going to be taking off the nut I am putting a new washer on

Sure seems like they could've give us just another half inch of shaft with a hole drilled through it, so they could put on a castellated nut and cotter pin.
Then sprockets flying off would be just about impossible.
Don't get me wrong. On the whole, it's a wonderfully designed piece of machinery.
But in this case, I think we got short shafted.:whistle:

I doubt the nut needs to be replaced if it is in good shape. The normal reason for replacement is that it is rounded off and someone took a chisel to it to split it or didn't change the front sprocket after rounding it off and just ignored it. One issue to consider is that many aftermarket countershaft sprockets will not have a hole drilled for sticking the tab on the washer into and thus the washer is a waste of time as far as its ability to provide a mechanical lock. I ALWAYS use red Loctite on those nuts.

Post edited by: wiredgeorge, at: 2007/02/21 16:38

Thanks George. Yeah I'm just going to use the original nut. And I plan on using some red Loktite along with the original washer. I'll torque it to virgin German girl specs (gootentite).

riverroad wrote:

And I plan on using some red Loktite along with the original washer.

The reason the original was so tight might have been because the torque windup from the countershaft output kept twisting the nut tighter. . .red loctite would probably prevent that in the future. Glad you got it fixed.

Yeah I figured it was either torque windup or a couple really big Japanese guys with a nine foot torque wrench.:lol: I'm definately not going to try and reproduce that much torque on the install.