I rode with my chain way too tight....

[motojoe_23]

Body weight wouldnt matter. It has no bearing on how the suspension travels. A tiny guy will nearly bottom the rear shock just as easily as a big guy if a jump is landed on the flat. Both riders have now pushed the chain to and past its tightest point... it still needs the same slack.

[grayracer513]

i looked at the pictures and even tho that is the minimum tension it still looks too loose.

That's why people over-tighten the chains on the new bikes.

i run my chains just a little tighter than that ( not by much)

Then you run yours too tight.

is that how you run your chains or is that just a example of the minimum tension?

That's how I run them, and that is the minimum tension that should be on that chain. The minimum tension spec on an '06 or later YZF is 1.9", and my block is only 1mm thicker than that at the point shown. That is what Yamaha calls for. MINIMUM means "the least", and the chain should never be tighter than that. If you drop the shock and swing that rear wheel through its travel, the chain will be nearly tight at the center point.

also i dont no if this is true but i had a thought about chains and your body weight.. lets say you weight 220lbs you should make yourchain more loose than you should if you weigh 180. like i said just a thought

Body weight makes no difference whatever. The suspension arrives at the point where the chain is tightest when it has traveled only about half way through its full swing. Beyond that point, it gets looser again. Besides, the spring rates are adjusted for body weight, anyway.

[rayivers]

I always wondered what would go down if the chain were run too tight, and didn't then break or stretch enough to make a real difference. Did I read correctly that a number of spokes pulled out of their nipples, and new sprocket teeth bent over? Wow, that's some seriously scary force in my book.

If it were me, I would rip apart the entire rear end and inspect the hub/spokes/nipples really well, every rear suspension bearing, the axle and tensioners, the swingarm pivot and linkage, the countershaft, everything - I'd even check the swingarm for twisting or bending. Maybe that sounds ridiculously anal, but I wouldn't want to miss something and end up being stranded in the middle of nowhere by related failures for the next few rides. Inspections can't hurt, but not doing them can.

Ray

[godhappan]

well the good news is that I was riding very conservatively, as I was alone, aside from a few short top outs, and I hit no jumps, just flat gravel roads. probably averaging 35mph.

the bad news is my chain was probably at the perfect setting, before my adjustment according to those photos...

the spokes weren't pulled out of the nipples, they just loosened themselves, probably from the small bumps I was going over and the lack of travel; and the previously unchecked spokes.

I gonna replace the drive, get it the rim trued, possibly making an excuse for a black excel, inspect the hub/spokes, run it and keep an eye on things.

will a 99-2001ish yz400 hub fit on my bike?

does replacing the countershaft seal involve splitting the cases?

[grayracer513]

will a 99-2001ish yz400 hub fit on my bike?

does replacing the countershaft seal involve splitting the cases?

Second question, no. Just the removal of the sprocket.

As to the first question, not knowing what kind of bike you have makes that hard to answer definitively, but here's the scoop:

https://www.thumpertalk.com/forum/showthread.php?t=632582

[kawazooki_doc]

in regards to the minimum measurment being 1.95"...you need to check for what your particular manufacture calls for. My 05 rmz shop manual calls for roughly a min of 2.05, and a max of 2.50. I say roughly becuase I don't want to look right now, but I know for a FACT it requires more than 1.95 for my bike.

Okay I looked it up so I don't get bashed...lol its 2.05 and 2.44

[grayracer513]

Your point is well taken, but in as much as this is the YZ450 forum, I thought it would be OK to post specs for them and not RMZ's.?

Seriously though, each model, even each Yamaha model, has its own specification, and when the factory tells you not to go tighter than a certain setting, measured a certain way, it is critically unwise to believe you know better, or not to pay attention to the details of how it's measured.

[matt4x4]

Inspecting the countershaft bearing is relatively simple, pull the countershaft sprocket, grab the countrshaft and see if there is even the tiniest bit of play in any direction - side to side will likely be a culprit, if it does have any play - even 1/10th of a mm, the bearing will continue to wear until it breaks since it is a part that continually gets a ton of force applied to it.

The seal can be pulled off from the outside but does not need to be pulled for checking the shaft/bearing play.

[grayracer513]

Inspecting the countershaft bearing is relatively simple, pull the countershaft sprocket, grab the countrshaft and see if there is even the tiniest bit of play in any direction - side to side will likely be a culprit, if it does have any play - even 1/10th of a mm, the bearing will continue to wear until it breaks since it is a part that continually gets a ton of force applied to it.

Removing the chain is all that should be done. If the sprocket is removed, depending on the fit of the shaft to the bearing, up to .100" or more of end play may be detectable as a result of the shaft sliding in and out of the bearing that has nothing to do with the bearing's condition. Better to leave it bolted up. It is correct to say that there should be little if any play at right angles to the shaft axis (up, down, fore, aft), but there is likely to be up to .010" of end play (in/out) in an otherwise healthy ball bearing that size, so don't get too disturbed by that.

[Birdy426]

As far as inspecting the hub, while you have the sprocket off, most automotive machine shops can do a Dye Penetrant inspection for cracks on the sprocket mounting holes and ears fairly cheaply, liek maybe 25 bucks or so. Good, cheap insurance.

[godhappan]

no play whatsoever in the sprocket counter,

Is this "dye" something I can do/get myself?