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PROPER Springs

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Just want to give everyone a real strong urging to have someone help you when measuring rider and static sag. Can't emphasize this too much. I have a very nice bike which I have kept for 10 years for the motor, handling and total reliability. 01 Honda CR250 that is still very capable and competitive. Especially in my SR hands. But, for those ten years I have been beaten to a PULP by the suspension. None of my buddies live near me so I have been attempting to do the measuring by myself. Thought I was being accurate but have found that was a joke and wasted a lot of riding pleasure. With that lost pleasure went a boatload of money on failed revalves. But, I am sure the revalves were probably not really failed, it was my inaccurate measuring process that was preventing the spring/valving combination to work properly. That caused me to give bad info to my tuners. So, please get a good buddy with good eyesight and a good measuring device. Find a place to balance yourself while STANDING ON THE PEGS in a straight up and down fashion. Next to a wall or something that does not cause you to lean. DO NOT lean over the bars in the attack position, STAY in a straight up and down position over the pegs. Take VERY careful measurements in this position. Do not ever, never, ever, never sit on the seat and try to turn around and do this. NEVER. PERIOD. And of course it is understood you must have greased, properly working linkage. I finally ended up with the correct springs that have made a world of difference and will be able (I think) to dial things in with the clickers. Very, very close today. To end, I have to give a shout out and HURRAH to GD170 and KTMLew who have been VERY helpful and more than steadfast in helping. They both made generous offers to help that I will not forget. Do not mean to overlook others with good suggestions but these two guys really jumped in with both feet. Good guys! :bonk::smirk:

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I've built many race bikes both in roadracing and motocross. I've set sag on hundreds of bikes and the difference between standing/sitting and doing it yourself vs holding the bike, are all minimal. I'm not gonna say that doing it yourself is better, having someone do it for you is the best way by far, its more accurate in a single pass. I usually measure two or three times when I do it myself, just to make sure. At the same time though, if you know how to do it properly, the numbers will be accurate.

How I measure sag on dirt bikes that you own, is quite simple. I get on the bike with a stand next to me and I preload the entire bike using the foot peg a few times, making sure the front and rear go up and down. Most importantly, that they don't go all the way back up again, thats part of the trick. Once the bike is in its settled position, then you sit on the seat all the way forward and then take the foot that was on the stand, tip toe it on the ground. I have the proper sag measuring tool and what I do is turn around and with my left hand I inch down the tool with my thumb and index finger until I feel fender/tool mating spot where the number and the fender meet. Then I turn facing forward, take my foot off the ground and in that second before the bike falls over, I inch my finger down the tool until I feel the fender/tool mating spot and it hits the correct number. Then I put my foot back on the ground, turn around and pull the tool off and read the number.

Yes, your foot has to be off the ground to measure accurately. Luckily these are dirt bikes and they don't weigh that much so having your foot off the ground is not that difficult do accomplish.

Yes, you can do it yourself with the proper tools. I use a Race Tech Sag master tape measure. I put the L bracket on the bottom of the tape into the hole of the axel and pull it up, putting tension on it and drape it over the fender. The weight of the tape measure keeps it in place pretty well.

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If you use barkbusters just hook a tie-down to one side and attach to a solid object like your truck or bench. Adjust tie-down so the bike leans just slightly to the left. I like to hold rear brake while checking sag.

I use a sag scale. Insert pin in axle and as suggested above, finger mark the fender/scale. Clip a small pair of vise-grips on the fender to rest the scale against so it stays vertical...

Then when you go on a ride have someone re-check for you. This is also why I set static first. Then ride the bike while adding/reducing preload to see what steers/accelerates out of corners best.

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If you use barkbusters just hook a tie-down to one side and attach to a solid object like your truck or bench. Adjust tie-down so the bike leans just slightly to the left. I like to hold rear brake while checking sag.

I use a sag scale. Insert pin in axle and as suggested above, finger mark the fender/scale. Clip a small pair of vise-grips on the fender to rest the scale against so it stays vertical...

Then when you go on a ride have someone re-check for you. This is also why I set static first. Then ride the bike while adding/reducing preload to see what steers/accelerates out of corners best.

Thanks again. What number for static do you start with? The vice grip thing sounds helpful. But, do you not think the twisting and turning has an effect? :bonk:

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On a linkage bike 32mm. Then reduce preload until steering suffers. If you end up at more than 45mm static you probably could use a softer spring.

A too soft spring will need extra preload to steer decently and will then have less than optimal static sag. (under 30mm IMO)

Aluminum frame bikes suck...make it difficult to adjust preload, carb work, harsh feeling, etc...

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On a linkage bike 32mm. Then reduce preload until steering suffers. If you end up at more than 45mm static you probably could use a softer spring.

A too soft spring will need extra preload to steer decently and will then have less than optimal static sag. (under 30mm IMO)

Aluminum frame bikes suck...make it difficult to adjust preload, carb work, harsh feeling, etc...

No argument here. :bonk:

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