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Sag checker

_RG_

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I'm a proud member of the camp who believe motorcycles these days roll off the line with some pretty good suspension components. Our ilk also holds that folks should get out their manual and tinker with the suspension before dropping $2500 or more on having some shop swap out parts. Now if you're Cody Webb or Tristan Hart then politely ignore all the above as uninformed gibberish. For the rest us mere mortals however...

Folks who do suspension work all day and dream about it at night are emphatic about setting your riding sag before even attempting to tinker with the dark arts of compression damping and rebound.

One of the crew's wife gave him a wireless sag checker. Really nice...and pretty expensive for something that's likely going to spend 99% of it's life parked in the toolbox. Once your sag is properly set why change it unless you and Little Debby pack on another 50 or so around the tail bone?

So who's used the tape measure technique? It's ok...nuthin to be ashamed of. Takes about one session to decide there has got to be a better way. Of course there are a number of products out there that help. Here's one of them:

20220326_190215.jpg


Little cable spring wound with a sliding stop. Attach one end to the axle hole and the other above it on some plastic.

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You'll really want a bike lift for doing this. You young husky fellows who can throw your bike over your shoulder might get by with borrowing a milk crate from a klr rider but the rest of us will appreciate an easier way to raise and lower the motorcycle. You'll get to do that several times.

Nothing new here...raise the bike...set the stop down on the base unit...lower the bike...get on (with gear or comparable weight)...gently get off the bike and measure the distance from the base unit to the sliding stop.

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So...does this product work? Sure. I had to adjust the stop (made to be adjusted) so that it slid easier but caught well enough to stay put when I'd get off the motorcycle. And...you need some way to measure that distance. So really this tool is only part of the solution. Since we're talking mm here something reasonably accurate helps.

You need a way to sit on the seat in riding position with both feet on the pegs. Gravity makes this part tricky.

Can one person check the sag without two or three semi sober riding chums standing by? Yeah...no prob.

Is this tool worth the $35 price? Just barely but it does work as advertised. I don't expect it will take a lot of abuse. I'm concerned about the spring inside behaving like every tape measure I've ever owned... but maybe not. Now...on to the dark arts.
 

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I've been using this one for years, it does require two people.
Sag is the first thing to set before any suspension work, unless you are way out side the weight range of the bike.
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I've has my 350 for 3 years . Probably should look into this settings . It does all the trails around Austin so it can't be too bad. Just ride it the way they gave it to me. Sacrilege I know 🤣
 
Same here. Never have checked it on any bike I've ever had, but know that I should. Keep saying I'll do it when my weight stabilizes :uhoh:
 
I've been using this one for years, it does require two people.
Sag is the first thing to set before any suspension work, unless you are way out side the weight range of the bike.
View attachment 316737

Some of us are always way outside the range for the bike's stock springs... It really doesn't help that team Japan always springs US market bikes for a 140lb featherweight.
 
Some of us are always way outside the range for the bike's stock springs... It really doesn't help that team Japan always springs US market bikes for a 140lb featherweight.

Featherweight? That is almost exactly the worldwide average adult male's weight. US average is closer to 200 lbs. Most bikes are sprung for ~ 180 lbs. I don't think they spring differently by market so their weight target is actually favoring us.
 
A tape measure and wife/buddy will do the trick! My 1250 Bandit, ZX14 and GSX S1000 all benefited from my adjusting sag and then compression/rebound.
 
Tape measure for years, used a buds sag stick last time, interesting thing is go to any pro mx pits and 80 percent of them still
use a tape measure
 
Makes sense...tape measures works. Unless you're short on extra folks around to help run it. We've read magazine articles about some character who swears that the difference between 105 and 107 mm just made all the difference in handling with his motorcycle. I'm skeptical. I get the part about how we want the bike to stand up so the suspension has a full stroke to travel...forks and shock. I'm guessing the prescribed sag setting puts the shock at that happy medium where it's not bouncing like a pogo stick but still optimizes the stroke length. And it's different for each rider depending on their weight. I'm still trying thrash all this out...:scratch:
 
RG, its funny I have the exact same sag checker. I did a lot of looking and it seemed to be the best value proposition.

Remember sag is only part of the issue. If you have to jack up your preload to get a proper sag setting you may have the wrong spring to begin with and you have more than likely blown past the compression and rebound setup too. Suspension is the single best thing you can do to improve handling.
 
My son gave me this for Christmas. Doesnt get any easier. I check my sag about 2 or 3 times a yer. Its never the same either. Not off by much but off.

Motool Slacker Digital Suspension Tuner V4 with Wireless RemoteScreen Shot 2022-03-29 at 12.50.25 PM.png

 
I have a piece of aluminum flat bar I clamp to my swing arm and put a mark on with the bike on the stand. I then calculate where it should be with just the weight of the bike and then me on the bike adding marks for these two points. Then I drop the bike and check then get on the bike and check by just looking back at my mark.

I usually do this after I service the suspension for a starting point. When you think about what sag does and why it is important. It was mentioned that it keeps your shock it it’s proper place in the stroke. It also effects the rake of the forks. Some design genius somewhere came up with all the geometry of the chassis of this rocket ship your piloting. When the sag is set to the factory spec everything is just like the design guy intended. That’s all fine and good until the real world hits and you change tires and the height is slightly different or you are really aggressive sliding forward in turns and not where your weight was when you set sag. I will change mine a few rounds up or down depending on terrain and how aggressive I’m riding. If the bike is running wide and not turning in like I want I add pre load which will make the forks steeper and the bike will turn quicker. In the event it is turning in too quick or trying to tuck the front, just back a couple rounds out and slow the steering just a bit. Sometimes it can be fun to twist on things to see how the bike responds and sometimes it’s fun to set it at home like it was designed and just ride.
 
Makes sense...tape measures works. Unless you're short on extra folks around to help run it. We've read magazine articles about some character who swears that the difference between 105 and 107 mm just made all the difference in handling with his motorcycle. I'm skeptical. I get the part about how we want the bike to stand up so the suspension has a full stroke to travel...forks and shock. I'm guessing the prescribed sag setting puts the shock at that happy medium where it's not bouncing like a pogo stick but still optimizes the stroke length. And it's different for each rider depending on their weight. I'm still trying thrash all this out...:scratch:
2 mm is .07874!! Under a tenth of an inch!!
 
I'll bring this gadget along with a lift etc. to the gathering in Kerrville at the end of April. If anyone wants to set their sag we'll knock it out while you're there.

That's a great idea, Greg. Thanks for offering.

Years ago, Tourmeister and a handful of onlookers, helpers, supervisors or mebbe just half-drunk knuckleheads set the sag on my Wee.
 
I have a piece of aluminum flat bar I clamp to my swing arm and put a mark on with the bike on the stand. I then calculate where it should be with just the weight of the bike and then me on the bike adding marks for these two points. Then I drop the bike and check then get on the bike and check by just looking back at my mark.

I usually do this after I service the suspension for a starting point. When you think about what sag does and why it is important. It was mentioned that it keeps your shock it it’s proper place in the stroke. It also effects the rake of the forks. Some design genius somewhere came up with all the geometry of the chassis of this rocket ship your piloting. When the sag is set to the factory spec everything is just like the design guy intended. That’s all fine and good until the real world hits and you change tires and the height is slightly different or you are really aggressive sliding forward in turns and not where your weight was when you set sag. I will change mine a few rounds up or down depending on terrain and how aggressive I’m riding. If the bike is running wide and not turning in like I want I add pre load which will make the forks steeper and the bike will turn quicker. In the event it is turning in too quick or trying to tuck the front, just back a couple rounds out and slow the steering just a bit. Sometimes it can be fun to twist on things to see how the bike responds and sometimes it’s fun to set it at home like it was designed and just ride.
:thumb: :thumb:
 
I took a yard stick, drilled a hole about 2" from the end, put an old Cycra bar end bolt in there and stuffed that in the axle hole. Tighten the bolt a bit so there's no slop.

Took blue painter's tape and marked the starting point on the yard stick.

You can do static by yourself. Maybe get help for rider sag, or record it with your phone, etc.
 
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