Rear Suspension Swap
- Thread starter gatdammit
- Start date
Joined Mar 2013
3K Posts | 161+
Naples, IT
I'm kinda battling the suspension. No matter how much I soften the front and rear up, it still hits pretty hard on bumps. I'm not backing the compression all the way to 0, but I've dialed out quite a bit in testing and I just can't get rid of "thunk". It's not bottoming out, I just kind find a comfort zone.
I also have a bit of the accordion affect when hitting bumps in aggressive sweepers. Like, front tucks a little and rear kicks a little (think of the letter "Z"). Occasionally, it feels like the rear walks out a bit during slow speed leans, like a sliding sensation. It's got me a little spooked and my confidence is rattled. With the Andreani front/ OEM rear I had for years, I had not problem taking her to the bitter edge and holding tight lines in sweepers.
The rear is easy to reset but I'm scared to fiddle with the front adjusters too much. I don't want to back a screw all the way out and I've read bottoming them can damage the cartridge. I'm not a great suspension tech and have been struggling with test and tune. I feel like the compromised position of new rearsets - highest setting - kinda has my weight distribution off. I also feared my rear kit bag was too heavy (about 8.0 lbs). I normally have 10-15 lbs of luggage weight.
Any tips are appreciated.
I also have a bit of the accordion affect when hitting bumps in aggressive sweepers. Like, front tucks a little and rear kicks a little (think of the letter "Z"). Occasionally, it feels like the rear walks out a bit during slow speed leans, like a sliding sensation. It's got me a little spooked and my confidence is rattled. With the Andreani front/ OEM rear I had for years, I had not problem taking her to the bitter edge and holding tight lines in sweepers.
The rear is easy to reset but I'm scared to fiddle with the front adjusters too much. I don't want to back a screw all the way out and I've read bottoming them can damage the cartridge. I'm not a great suspension tech and have been struggling with test and tune. I feel like the compromised position of new rearsets - highest setting - kinda has my weight distribution off. I also feared my rear kit bag was too heavy (about 8.0 lbs). I normally have 10-15 lbs of luggage weight.
Any tips are appreciated.
Joined Mar 2013
3K Posts | 161+
Naples, IT
I actually factored my riding weight plus 15 lbs of gear when I ordered the rear. I am reluctant to mess with the spring preload. You'd think having simple adjusters would make this easy...
Also no expert - had a bit of practice on a MTB which has the same general principals. If you're getting thrown about and it feels like you're getting a different rate front to rear, then I would start with setting your sag so that both ends compress the same with your weight on the bike. Hard to measure but can be easier with a camera side-on. Then you need your rebound rate to be the same too. On a mountain bike we'd just load the suspension with our weigh and feel for it popping back evenly. Harder to do on the 'Strada. might be easier if you can get your front wheel into a chock or something? Again, easier with a camera filming you side on.
The nice thing about these is that you don't need to change the forks, you can just match your rear shock to them. Just question if you're happy with how the front end is behaving over bumpy stuff before you match the back to it.
The nice thing about these is that you don't need to change the forks, you can just match your rear shock to them. Just question if you're happy with how the front end is behaving over bumpy stuff before you match the back to it.
Joined Mar 2013
3K Posts | 161+
Naples, IT
Enreves, that's great advice. I feel like they are fighting each other but I'm officially lost on which dial to turn which way. Every time I think I understand compression and rebound, I get conflicting results.
Definitely a two man job and I'm not going to pay a shop for it. I've watched countless vids and read tons of articles about dialing it in. I'll get another set of hands and sort it out.
Definitely a two man job and I'm not going to pay a shop for it. I've watched countless vids and read tons of articles about dialing it in. I'll get another set of hands and sort it out.
Second Dave Moss, his videos are great and remote tuning is better than you'd expect, assuming you can work out the time zone difference. Dave set up my bike (and my 3 years fatter *** needs to have a checkup from him soon) and it rides great!
Yes, he does vido chat diagnosis, and also reviews pictures you send him. I'm a typical american and can't place his accent as to where he is from, but he lives in Northern California which is a treat for those of us who also live here as it's easy to find him a track nearby for a quick suspension setup.
Don't be afraid to turn your adjusters. The whole thing about damaging them is from turning them tightly once they hit the end point and stripping out the tiny little mechanism. The only think you want to be careful of when turning your adjusters is to not dial in too much rebound damping, especially up front. This will cause the tire to "pack up" because it can't extend quickly enough, thus steepening your steering angle and making the bike more prone to a tank slapper. Other than that, you can't hurt anything and you should really experiment to know what each thing does.
With regards to your harshness issue... you have to follow the basic process:
-Are your springs correct? This can be determined by measuring sag. I suspect something in the .85kg/mm fork spring and 95N/mm shock spring is correct for a 180lb rider. The bike should sag about 10% under its own weight, and a total of 30% with you on it. Once the springs are correct, adjust preload so this parameter is met.
-Is your fork aligned? An insane amount of front-end harshness can be caused by the fork tubes not being perfectly parallel and thus inducing friction. This is easily fixed by loosening the one side of the front axle pinch bolts and making sure the leg moves freely, then re-torquing in a neutral steering position.
-Set the adjusters back to the middle position. Go for a ride
-Open the adjusters fully, go for a ride
-Set the compression adjusters fully closed, go for a ride.
-Take notes each time.
And don't ask Dave Moss, you'll spend money and won't learn a damn thing.
Read this instead: Race Tech's Motorcycle Suspension Bible.pdf [2nv82rdmdylk]
Joined Mar 2013
3K Posts | 161+
Naples, IT
Thanks again, Kuk. I haven't done basic sag setup since installing rear, but fronts were pretty dialed in before that swap and the shop that sold me rear set it based on lots of anthro data.
Overall, it's very stable. I just want it to soak up bumps a little better, especially in sweepers. I've been twisting the dials more and more and noticing everything except soaking up bumps.
Appreciate the reading material.
Overall, it's very stable. I just want it to soak up bumps a little better, especially in sweepers. I've been twisting the dials more and more and noticing everything except soaking up bumps.
Appreciate the reading material.
Hey Menti,
I've got a 13' hyper and would like a lower version shock...trade? Wonder if it is a compatible switch?
Joined Oct 2020
76 Posts | 11+
Santa Rosa CA
Dave Moss set up my 939 for a previous owner who weighed in at approx 125lbs (a slim young woman). Rear preload and rebound is backed off completely. Feels like truck and I’m 195! Front very soft, hopefully to suit her weight.
The front can be fixed by spacer and oil weight possibly. Heavier spring if needed.
Rear shock/spring? Seems like total replacement required.
Rear stock shock has rebound adjustment I think. That plus pre-load was actually enough (ala Dave Moss) to make the bike feel very planted. I think Dave also moved the front forks, though I can't recall if he raised or lowered them a few MM. Bike was great until I started out riding the fork entirely. I considered drop in cartridges which, based on folks feedback here would have worked fine. But I was feeling foolish and instead upgraded to a SP with all the pretty Ohlins bits.
Joined Oct 2020
76 Posts | 11+
Santa Rosa CA
I’m not inclined to drop big $$ into the bike. Also, dunno if I have your perseverance!
It's pretty well sorted at the moment for my purposes, of course now that I've got 25k on the bike it's time to start working on some maintenance items. First thing up is to service the fork and shock as I am sure the stock fluids are toast by now.
