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Progressive Lowered Fork Springs

17K views 20 replies 10 participants last post by  Dallas09America 
#1 ·
How much does the progressive lowered fork springs lower the front? What size rear shock should I get for the bike to sit level....lowered in the front and lowered in the rear.
 
#2 ·
In case anyone else whats the info. I called progressive. The front lowering kit comes with a 1 or 2 inch drop. The speedmaster has a positive rake in the front so the front is 1" higher that the back.

So If you go 1" drop in the front and 1" drop in the back the bike will sit similar to stock but lower with a positive rake.

If you go 2" drop in the front and 1" drop in the back the bike will be level.
 
#3 ·
Go with a Progressive 412 series in the rear. It dropped mine about 2 or 2 1/2 inches. The ride is a bit stiffer (fells like your part of the bike) but, the handleing isn't too badly compromised. just get used to scrapping the pegs before you go on a twisty road.
 
#6 ·
Thanks Roy.

1. Do you know if you need a spring compressor to take the shock out? I imagine the shock is under compression, I am not sure.

2. You may be better off to measure the height of the horizontal arm where the rear fender is mounted. It may give more accurate drop height.

I need mine lower to be more comfy when I stop. I am thinking just do the rear unless the handling is worsen.

Keep us posted. :)
 
#7 · (Edited)
1. Do you know if you need a spring compressor to take the shock out? I imagine the shock is under compression, I am not sure.

No not needed. Shocks on the America are of a basic design with basically an inner and outer tube held together with a damper rod that is secure with a bolt from the bottom of the fork. And then of course the spring and spacer, seals, etc. Disassembly is basically remove forks from bike, remove top cap to drain oil and remove spacer and spring, remove damper rod by removing damper bolt from bottom of fork. Lowering kit then adds one or two new damping springs (depending on if 1 or 2 inch lower desired) to damper rod which is then reinstall, then new main spring and spacer and oil. No need to separate inner and outer tubes or remove seals.

2. You may be better off to measure the height of the horizontal arm where the rear fender is mounted. It may give more accurate drop height.

That is a good idea. I will most likely take some before and after measurements from several locations. But most important for this change to us is the seat height. Reason for making these changes is to improve wife being able to reach ground when seated.

I need mine lower to be more comfy when I stop. I am thinking just do the rear unless the handling is worsen.

I was also only thinking about doing the rear, but the America already has so much rake in the front (which from my research will only increase if only lowering the back) that it tends to want to 'fall' into turns at slow speeds which my wife has a problem with already. After talking with Progressive I am even thinking about lowering the front 2 inches instead of just the 1 we are doing in the rear. This should reduce the front rake and improve slow speed handling but not adversely effect handling at speed.

Keep us posted. :)

Will do, plan is to document the whole change over to help others that are thinking of doing this.
 
#8 ·
I installed the 12” 412’s on the rear and purchased the Progressive front lowering spring kit but I just installed the progressive springs a slid the tubes up 3/8” in the tree’s. I was nervous about removing the damper rod and installing the lowering springs. It looks and rides fine but I would like to install the lowering springs one day. I hope you do step-by-step on the front.

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#15 ·
Fair question, my persoanl thoughts/reason for this project.

First is to understand this thread is primarily about replacing front springs to 'lower' the bike not necessarily to improve suspension. So even if the intiminators were part of the project the springs would still be replaced. And the Progressive lowering kit 'should' improve the suspension.

For me the main reason for this project is to lower my wife's bike so she can be more 'flat-footed' on the bike as she is haven't some major slow speed issues handling the bike. So we are lowering the rear with some Progressive 412's so we need to also lower the front, thus new lowering kit with new springs.

While I also what the best bag for the buck I know the Progressive shocks and springs will improve the suspension. I also looked at doing the Ricor's at the same time. BUT the Ricor's (off the top of my head) are about $300! After already spending about $350 for the shocks and lowering kit another $300 wasn't going to happen.

My wife doesn't need a 'racing' suspension setup, the bike will be lower, and we will see overal suspension improvement both front and rear for about the same price as the Ricor's alone.
 
#17 ·
i lowered my 05 speedy at the back, from 12.5 inch to 11.5 inch, with hagon nitro shocks. hagon make them to your exact weight and if you ride 2 up or carry a lot of luggage , they also take into account the kit you wear. i ordered them on a friday and they where delivered to my door the following wed mornin. perfect. 15 dampin settings and preload is an adjustable thread at the top which turns down until your basically happy. as with the progressive fork springs. i installed the 1 inch lowering kit. i had so much trouble trying to get the bottom spring retaining bolt out. you need a electric ratchet or air wrench and a brush sahft wedged down the tube. you only get one go or else it just spins forever. end result?. they lowered the front end, but really thats about it. they are still as spongy as ever at the front end. i just touch the front brake and the bike dives. so im not sure what to do to sort that out. thicker oil is a no go as it just defeats the purpose, so if anyone with any ideas, let me know. ps money is tight lol tks
 
#18 · (Edited)
Shocks and Lowering Springs Update (Kinda Long)

Might post some pictures later, but here's the results of this project...

Got the 11.5" shocks and front springs with 1" drop (more on this later) installed and rode the America to work yesterday with new configuration. Ride impression later in post.

Rear shocks took all of about 20 minutes to install with no issues at all. With just the rear shocks seat height was about 1 1/2" lower. But of course front end was still the same height so overall feel of the bike was even more chopper like. Not what we wanted!

Removal of front forks took about 30 minutes and was easier than I expected. Now the hard part, removal of the damper rod bolt to remove the damper rod. I had researched this extensively for the last few weeks and had all the tools and tricks I had learn via the internet ready to go.

Got the first fork setup in the vise put a 6" long allen socket on the impact wrench and gave it a go. Damper bolt and rod both just spin!

Ok, let's try the dowel/broom stick trick to keep the damper rod from spinning. Tapered a 1" dowel I had and stuck down the fork tube into the damper rod. Still a no go, bolt would not break loose. :(

Put the fork back together and compress the spring to see if this would hold the damper rod enough to free the bolt. Nope! :mad:

Try various other attempts over the next hour or so but that damper bolt would not bulge. Make the decision to take the forks to the dealer and have them free the bolt and install the kit with a 2" drop in front to level the bike as indicated by Progressive tech support.

Dropped them off on Saturday and they were going to do them on Tuesday morning. Got a call about mid-morning from the dealer with bad news. Even they could not get the bolt to break loose! :eek:

They were going to have to drill out the bolts and replace with new bolts and get them torque properly when reinstalled. BUT, they didn't have any bolts in stock and neither did Triumph America, would have to order bolts from UK, 7 to 10 days to arrive. Oh well, authorize the work and resigned to waiting for up to 2 week to get bike back together.

Mid-afternoon Tuesday got another call from dealer forks were ready to be picked up! They tried again before drilling out the bolts and were able to get the bolts loose. :D

Picked forks up Tuesday evening and would install on Wednesday. Take a look in the box the springs came in and what the...

There were still 2 damper rod springs in the box and for a 2" drop as I requested there should not have been any damper rod springs left! :mad:

Talked to the dealer on Wednesday morning and sure enough they didn't read the instructions correctly and just removed the stock damper rod spring and put two Progressive damper rod springs on instead of putting the two springs on IN ADDITION to the stock spring. Confirmed with the dealer that they did however put the correct length spacer in for a 2" drop. So now I have forks with spring for a 1" drop but the spacer length for a 2" drop. Dealer was very sorry and wanted to make it right.

However, before taking the shocks back in I called Progressive and discussed the issue and they indicated that the shorter than recommended spacer was not really a problem. Front damping would just be a bit on the 'soft' side and front would set just a small amount lower.

So it was decided to reinstall the forks just to see how this combination would be. Happy to say height of bike was just perfect for my wife and front end of bike was now sitting just about perfectly level.

So with dealer's approval and commitment to still fix if we wanted after getting a few miles on the bike we have decided to not have the 2" drop installed.

Ride Impression:

First off remember this is my wife's bike...

Installation has lower the bike an average of 1 1/2" at all points on the bike that I measured. This now allows my wife to flat foot the bike.

Rode around the block a few times Wednesday evening and initial impression was very good. Bike rode much better in my opinion with the front end lowering. Ground clearance definitely affected and I was able to bottom out the front with hard braking over a bump.

Rode to work on Thursday (7 miles city streets) and confirmed that I really like the ride and handling better with the lowering front end.

However, I do feel the front end is too 'soft' and I think I will put a longer spacer in. But this is not something that I will do right away. I weight just a bit more than the wife :) so I think I'll let her get some miles on it first.

Overall very pleased with the results but will caution for anyone doing this ground clearance will be affected so be careful.
 
#19 ·
Change out or cut OEM spring collar

New here. Thanks a million to everyone who have previously done all the testing, design and research. I was looking at the Bandit "OEM Parts - Triumph America 2009" parts break-out. I need to lower the front about an inch to level it up (on my '09 Amer). Could I replace the OEM collar shown in the pic with some PVC?
 
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