Help Me Understand Suspension
Thread Starter
|
Cruiser
Joined: Jul 2007
Posts: 205
Likes: 8
From: Louisiana
Help Me Understand Suspension
Ok guys, I need some input on suspension setup for my '07 Street Glide. In 2010 I put on a set of custom wheels with a 21" front wheel and an 18" rear wheel. Rode it like that for a long time. The main problems I had with that set up was when going over grooves cut in asphalt as lane crossing warnings, the front end would wobble, if going fast it was scary. Second, when riding roads with lots of twists and turns it seemed constant steering inputs were needed to ride smoothly (the complete opposite of the sport bikes I used to ride.) I recently put on new tires (Michelin Commander II) front and rear. I also installed Progressive mono tubes and lowered the front 1". My indy mechanic said that if I did not lower the rear at the same time, the ride would suffer. He said all the things I described above were due to the geometry being off after changing the wheels. So while riding home after the new tires, mono tubes and lowering blocks on the rear, I noted the bike seemed to track much better but the rear was bottoming out on some rough spots in the road. When I got home I checked the air pressure in the rear shocks and found there was only 15 lbs. of air. I put in more air hoping to stop the bottoming out, but I know the ride will be more harsh. My question is would new rear shocks help? If so should I remove the lowering blocks and use a 12" shock like the Olins or Progressives, or would the new shocks still need the lowering blocks? I realize the SG by nature of having less shock travel will not ride as smooth as the other touring models but I would still like a pleasant ride. When riding two up the load is about 400 lbs, which accounts for about 50% of total riding time. Any suggestions appreciated.
Outstanding HDF Member
Joined: Dec 2007
Posts: 2,403
Likes: 20
From: Indy
Ok I am going to sound like a fan boy, but you should call Howard at Motorcycle Metal , this guy knows his stuff, and BUILDS custom shocks, like Ohlins, they will be built to your weight, which will not bottom out, because they will be set up correctly. I think you would enjoy the bike much more with custom shocks. His site is www.motorcyclemetal.com
Ok guys, I need some input on suspension setup for my '07 Street Glide. In 2010 I put on a set of custom wheels with a 21" front wheel and an 18" rear wheel. Rode it like that for a long time. The main problems I had with that set up was when going over grooves cut in asphalt as lane crossing warnings, the front end would wobble, if going fast it was scary. Second, when riding roads with lots of twists and turns it seemed constant steering inputs were needed to ride smoothly (the complete opposite of the sport bikes I used to ride.) I recently put on new tires (Michelin Commander II) front and rear. I also installed Progressive mono tubes and lowered the front 1". My indy mechanic said that if I did not lower the rear at the same time, the ride would suffer. He said all the things I described above were due to the geometry being off after changing the wheels. So while riding home after the new tires, mono tubes and lowering blocks on the rear, I noted the bike seemed to track much better but the rear was bottoming out on some rough spots in the road. When I got home I checked the air pressure in the rear shocks and found there was only 15 lbs. of air. I put in more air hoping to stop the bottoming out, but I know the ride will be more harsh. My question is would new rear shocks help? If so should I remove the lowering blocks and use a 12" shock like the Olins or Progressives, or would the new shocks still need the lowering blocks? I realize the SG by nature of having less shock travel will not ride as smooth as the other touring models but I would still like a pleasant ride. When riding two up the load is about 400 lbs, which accounts for about 50% of total riding time. Any suggestions appreciated.
Ultimate HDF Member
Joined: Mar 2012
Posts: 6,129
Likes: 143
From: Santa Cruz
Throw the lowering blocks away! SG already has limited travel in the rear. The lowering blocks change shock angle to make things worse. Ya can try changing shock fluid but a good set of longer shocks will make all the difference. I have heard horror stories with 18/21 combos. Changing the rear wheel to a 16/17 may help too.
Ultimate HDF Member
Joined: Jan 2008
Posts: 6,532
Likes: 132
From: SoCal
The 18" rear is almost the exact same size diameter as your 16" depending on tire selection but the 21" is about 2" taller on diameter compared to the stock 16" front. So you raised the front up 1" from stock with the 21" and adding the lowering blocks on the rear made it worse.. Lowering it 1" on the front brought it back very close to where it was stock if you lose those lowering blocks. Yes your stock rear shocks suck. I raised mine up 1" in the rear with 13" ohlins to gain ground clearance, rear wheel travel and superior damping. Almost any aftermarket 13" or 12" shock will be better than the oem air shocks.
Road Warrior
Joined: Aug 2009
Posts: 1,630
Likes: 17
From: Central FL
By lowering the front and not the rear you changed the angle of the steering head which effects your rake and trail. Read up on those and you'll see how even the slightest change can have positive or negative results. By lowering the rear you will gain some stability but loose some of the quick response. For off the shelf rear shocks you could go with Progressive 940 series. They are 12 inch shocks but retain 13 inches of travel.
Thread
Thread Starter
Forum
Replies
Last Post
