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How do you guys measure the chain slack? I did the 3 finger thing on the top part of the swing arm pretty much right in front of the chain guard where it meets the upper chain guide. I did this with the bike in the air in neutral. Originally my big was set up by the dealer and the rear axle was off and living in the states I really only lean it on left handers. So my tire got ate up all crooked.  Anyway I moved it back, thought it felt too tight, moved it forward to tight. Now its a little more then 3 fingers but I have skinny fingers and the chain feels a little loose but the bike rides a little better as opposed to,, too tight before.

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sounds about right .. lean over the bike from the right side (with the kickstand down) and balance almost all your weight on it, reach down and feel the tension of the chain (remove the chain guard if you need to).. there should still be a bit of actual 'loose' slack, doesnt need to be much, but it needs to have alittle .. it wont hurt a thing if its a bit loose, 3-4 fingers at the top middle of the swingarm is ballpark close enough .. just be sure its never too tight, one shot running it too tight is enough to knacker a chain ..

Edited by cowpie

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Since the poster did not identify which model DRZ400 or sprocket set up, the best advise was to compress the rear suspension to align the countershaft. swing arm pivot, and rear axle and check to see there is stil some slack in the chain.  Universally works for all motorcyces and set ups.  Tendency is to have the chain too tight.  Much better to be a little loose rather than too tight.  Some motorcycles actually gain slack as the suspension compresses but for most the chain gets tightest 1/3 to 1/2  suspension travel.

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I did that with my DRZ, sucked the back down with a tie down till those three points line up, adjust to just a slight bit of slack, then back up on a stand and it's amazing, right in the middle of the manuals spec. 40-50mm

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8 hours ago, ohiodrz400sm said:

The actual measurement is 1.6- 2 " deflection measured on the bottom side of the swingarm between the sprockets.

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Yeah I was reading the service manual but this stuff is all so contradicting. What I got from it was put the bike in neutral and put the bike in the air then measure the rear chain on the bottom of the swing arm in the middle of both sprockets. The manual said 1.6-2" but is that from rest in one direction say up or total travel up and down?

 

The bike is 2014 DRZ400SM pretty much bone stock by the way 

 

The service manual also said 72.5 ft/lbs for the rear axle nut in the blue pages but the owners manual that came with my bike says 79.5, doesn't really matter but these manuals are confusing the shit out of me with everything.

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That's total movement. Pull the chain up. That's the zero point. Now push it down.

 

The blue pages (smk) applies to the SM and the differences vs the original S. In my 06 service manual, 72.5 is for the USA(E-03), California(E-33) and Canada(E-28) models. The rest of the world is 79.5

 

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Some markets get "castle" axle nuts (cotter pins).  Some get running torque nuts (no cotter pins).  May be the reason for different torque specifications.  It is really irreverent.  Tighten securely.

 

 

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Yeah I have been doing 73 ft/lbs and although I don't have that many miles its been fine with even a little highway. Mine is a US spec bike but the owners manual states 79.5 for my bike, maybe im reading the owners manual wrong but its just odd. Maybe a typo in the manual I don't know.

 

Edited by SKIPPY PB

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I'm of the opinion after having adjusted mine a few times over the four years I've owned it the owner's manual should state this measurement to be taken from the top of the swing arm at the end of the plastic chain guard.  This puts mine in the 1.6-2.0" range at this location and with all three points aligned I have a small amount of slack.  If I go off the bottom of the swing arm, it's way too much slop.  I just do the three finger rule, (or on mine 1 7/8") from the very back of the plastic chain guide on top of the swing arm to the widest point of a chain link lobe.  Works for me anyway. 

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2 hours ago, WesternMDMtnMan said:

I'm of the opinion after having adjusted mine a few times over the four years I've owned it the owner's manual should state this measurement to be taken from the top of the swing arm at the end of the plastic chain guard.  This puts mine in the 1.6-2.0" range at this location and with all three points aligned I have a small amount of slack.  If I go off the bottom of the swing arm, it's way too much slop.  I just do the three finger rule, (or on mine 1 7/8") from the very back of the plastic chain guide on top of the swing arm to the widest point of a chain link lobe.  Works for me anyway. 

im game, lets peel the cobwebs off this thread  .. i took a measurement and i run mine at about 2.5-2.75" at that location .. i think its possible it might vary by bike or gearing config on whats ideal to, mainly though, i think the suspension needs to be compressed to check that theres definitely alittle slack left compressed and the chain isnt getting stressed ...

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1 hour ago, cowpie said:

im game, lets peel the cobwebs off this thread  .. i took a measurement and i run mine at about 2.5-2.75" at that location .. i think its possible it might vary by bike or gearing config on whats ideal to, mainly though, i think the suspension needs to be compressed to check that theres definitely alittle slack left compressed and the chain isnt getting stressed ...

I just got to thinkin about it and was near they computer in my shop today after putting new shoes, air filter, plug, etc, etc.... on.  I found I'm going to be in need of a new chain soon.  This one will work for a while yet, but it's become a slight bit kinky in some spots even after soakin and workin with it a while.  I believe you're right about each setup maybe being a bit different and a lot of it may have to do with sprocket combo's as well.  Just remembered going over the bike right after I bought it and it never had that much slack under the swing arm brand new.  So I got bored and Thumpertalked the subject. 

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16 hours ago, WesternMDMtnMan said:

I just got to thinkin about it and was near they computer in my shop today after putting new shoes, air filter, plug, etc, etc.... on.  I found I'm going to be in need of a new chain soon.  This one will work for a while yet, but it's become a slight bit kinky in some spots even after soakin and workin with it a while.  I believe you're right about each setup maybe being a bit different and a lot of it may have to do with sprocket combo's as well.  Just remembered going over the bike right after I bought it and it never had that much slack under the swing arm brand new.  So I got bored and Thumpertalked the subject. 

yeah, chains are really something im still learning how to deal with in the best way possible .. ive been running a non-oring chain for about 5k on the street, it was going fine and i really only had to adjust it one time 'until' i got caught in some nasty weather .. i pretty much just sprayed it with some lube the next day and let it eat ..should have soaked it out in a bucket of gas first .. since then ive had to adjust it 2 times in a short period, took alot out of it that mistake ..

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