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Discussion Starter #1
Now that I have 500 miles on my new to me 03 Classic since last week Tuesday I already know suspension upgrades are on the list for this winter. I already know what I plan for the forks, but the shocks,....I need more travel and ground clearance. I've already grounded the floor boards on easy turns. I'm so used to leaning my BMWs to the edges of the tires I don't want to be limited by this bike relative to lean angle.

I'm only 5'-6" with almost a 30" inseam, and even on the Vulcan I feel like I need more shocks in the rear, like more travel and better tuning. Since one reason I bought the bike is for 2-up riding I plan to replace the rear shocks with LONGER that stock shocks, perhaps raise the rear of the bike 1.5". i also plan to raise the floorboards at least an inch if not 1.5".

I fully realize the effect on the steering geometry and fork angle, but since the forks stock are at 32 degrees a slight raise in the rear suspension will have no real impact on the steering to be concerned about. I choose handling over ride height all the time. I'm used to tall BMWs so this bike can is still plenty low to me. Anyone have experience with raising the rear suspension?
 

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I put progressive 444 on my 2004. Im the opposite, 6'4, 240 and I ride 2 up almost always. I got the HD model and really like them. I bottomed out the stock shocks all the time, scraped on every corner and since switching the ride is a huge improvement. You can order them in custom lengths as well, so lower, higher doesn't matter. I got stock height replacement. Now to tackle the front...
 

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Discussion Starter #3 (Edited)
Thanks for the info. I suspect the PO may have installed shorter than stock shocks. The shocks on my Classic are KYB brand which I doubt are original to the bike. I'll check the shock length and if they are shorter than stock I'll go with the stock shock length for the Mean Streak, which are typically 1/2" longer than the stock shocks on the Classic.

The fork mods are fairly straight forward and common:
1. Change the springs to progressive wound springs, which are softer rate for the initial fork travel but get stiffer as travel is used up.
2. Up size the oil holes in the damper rods, increase the hole size so the oil can move through the damper rods more easily, which allows the fork to respond better/quicker to small sharp bumps.
3. Use a lighter weight oil, like ATF or 15w fork oil, but install a lot more oil. Take the springs out and fully compress the forks, then fill with oil up to three inches from the top of the fork leg. Lighter weight oil makes the forks more responsive, more oil increases the damping rate quickly near the end of full fork compression to limit bottoming of the forks over big bumps/high loads. Reinstall the fork springs.
4. Before installing the fork caps, install a preload spacer on top of the springs to limit initial fork "sag" to about 1/2". Then install the fork leg caps.

I also plan to install air fittings into the fork caps so I can adjust the air pressure in the fork legs. About 15 psi of air in the fork legs add compression damping control and limit dive during braking.
 

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Discussion Starter #5 (Edited)
That is an upcoming project. In the past when I did this the spacers were at least 1.5" long, usually 3/4" size steel or plastic pipe coupler. Some times old valve springs from a VW Beatlle make great preload spacers. Generally, you want preload adjusted so the fork sag is about 1/2" when you sit on the bike, feet up. So it takes a bit of adjust/test, but generally the spacer preload goal is 1/2" sag.

For a pump, I plan to use a hand bulb, needle valve and gauge from a blood pressure test cuff. You can find them cheap on ebay, high quality, limited volume per squeeze, only need 15 psi like you said. And with the needle shut off valve you can leave it plumbed right into the system. Open the valve, hand pump the bulb to adjust the pressure or bleed pressure off, shut the valve off to separate the hand bulb and gauge from the system, go enjoy the ride.

I plan to use the same hand bulb, needle valve and gauge plumbed into the rear air shock system.

Oh, measured the rear shocks and they're only 12" eye to eye. So I'm installing a set of Nomad shocks with the air damping adjustment, which are 13" eye to eye. That still let's me totally flat foot the bike at stops. I prefer it to ride higher so I can get more lean clearance. I even plan to raise the floorboards 1" at least to increase my lean angle capability.
 
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