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....is rear ride height can change the trail distance but will not change the rake angle.
Is this correct?
The rake angle on the frame remains the same, but the angle in relation to level ground changes. That's why there's a difference in trail.
 
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OK... I went back and looked at the rake & trail diagrams and the way I see it :) is rear ride height can change the trail distance but will not change the rake angle.
Is this correct?
Yes... Alan Gots it... Level Ground..and Level Horizontal Frame Tubes
No Suspension changes... Including Removing them, Can Change the Neck Rake of the Frame...
Effective Rake... is what changes... and Only with Suspension, and a Front End, and Wheels...can we Measure Trail... Which is what Really Counts
There is a Reason that we did Not want Buells to Tie the front end Down and leave the rear High ... then go out and run over a 120 MPH in the 1/4... Those were Very Scary, Head Shaking Mo-Fo's... Not Nearly enough Trail with the front down and the ass up...We Like Big Trail Numbers for Straight Line Stability
 

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The rake changes. It's measured from a line that comes straight up from the level floor.

Up or down in the rear, you remove or add rake. Same for the front.

With that said, changing it at the rear is really a small change. If you want to see what a noticeable rake change feels like, Slip your fork tubes an inch higher in the trees. It'll be more responsive to input in the turns. But also on the straight, which will make it more twitchy. And it will make it prone to being a little evil at slow speed with a heavy bike.

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The Harley world worries a lot about the trail measurement. But of more importance is how far the rake line is behind the axel as it passes the axle center line. This is caster, and has a lot to do with front end stability.
 

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Only if the front is stretched, without the back... If Both Raised...nothing changes enough to consider it.
Positive you know this... but... wanted to clarify
It appears the rear is not raised as much as the front, here's Harley's specs-

FXRT, FXRS-SP, FXRS-CONV: rake/trail = 31/4.82

FXR, FXRS, FXLR: rake/trail = 29/4.22
 

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It appears the rear is not raised as much as the front, here's Harley's specs-

FXRT, FXRS-SP, FXRS-CONV: rake/trail = 31/4.82

FXR, FXRS, FXLR: rake/trail = 29/4.22
All well and good... But the Year model actually Matters, as well.. Any FXR Frame I ever investigated had exactly the same frame Dimensions.. Some small weldments, and the top shock mounts changed... but the Neck area (and Rake of the Frame itself) are identical...
The MoCo plays Fast and loose with these Numbers..Trying to Impress themselves Me Thinks
Lower the rear more Rake, Raise it less rake
Effective Rake!!! actually it is the Trail Numbers that Change
 

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Any FXR Frame I ever investigated had exactly the same frame Dimensions.. Some small weldments, and the top shock mounts changed... but the Neck area (and Rake of the Frame itself) are identical...
Yes, all frames have the same dimensions, the differences are in the suspension.
 

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My friend Morgan was like the 2nd car at this accident on Rt.30 (Townshend) where a women turned left (into River Bend store) in front of a guy on a Triumph. Basically a head-on and the guy was really messed up but talking. They choppered him out of an open field down the road (same one I went from) up to Dartmouth Hitchcock Hospital but Morgan said he didn't think he was going to make it. His legs were all twisted and messed up.
This is the 2nd time in like a week that someone has crossed centerline and taken out bikers. I'm going riding today and will stay to the right side of my lane. Good luck boys, they're still trying to kill us.


Morgan and my bike (pre-saddlebags) at River Bend parking lot.
 

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I generally ride the left side of the lane so I am easier to see and have room to move over to the right if needed.
 

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Sorry stuff to hear..
Note)1 I do Not like to lay to the outside of my Lane.. People aroud here feel that is an invite to Crowd you out/off.
I was taught to "command your lane"... but... maybe no one will try to sidle up next to You.
Note)2 I happen to Know (Personal Experience) that a Life-Flight is usually a positive thing. Even if they tell yer Family, that you probably won't survive the Flight..
Yer Not gonna have a Good Day tho
 

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I generally ride the left side of the lane so I am easier to see and have room to move over to the right if needed.
I'll ride the left until I get close to an oncoming vehicle. Then I'll drift to the right. Back to the left as soon as they pass.
 

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I've been doing a little of this and a little of that on my FXR.

Went back into the cam chest to address a little gear whine, and after the fact found out the second gen pinion gear supply has dried up. So rather than pay to have cam gears pressed off and swapped between cams, I just put the big cam back in.

Then I started in on all the upgrades I have been collecting up over the winter.

New shocks, emulators and new springs for the forks. Digital gauges (I think they have been sitting on my desk since Christmas.) And I'm putting four pot calipers all around. The fronts just required some store bought brackets and longer hoses. The rear is a little more difficult. I had to make a caliper stop out of steel strap, then weld it to the swing arm. Past that it just took a banjo to inverted flair adapter fitting. Still waiting on some parts, but it should be ready for Gettysburg Bike Week.

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My first time TIG welding steel that is thicker than a down pipe. Worked pretty slick, very clean, no slag mess to sweep up afterwards. Had to build a little offset into the bracket to counter the splay in the swing arm. Then the caliper wanted a little angle on the bracket to slide smoothly.

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Next up is rebuilding the calipers and getting black epoxy on the swing arm and rear caliper. Have to wait on that for a day the ole lady is in office. So I can bake them in the oven.
 

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I've got the same dual front caliper setup on my bike that you have on yours. Believe me, they WILL lock up the front wheel. They ain't pretty, but they do the job.
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Ya, I had them on my 2000 -4. Going from 3 pots to 12 pots makes a big difference.

My fronts actually worked well. It's the rear where the issue was developing. With each passing year the caliper got looser and looser in the bracket. It would sag and use most of the pedal stroke just closing up the sag. It needs to be drilled out and have a bushing installed. As cheap as these 4 pot calipers are now, I decided to just move the brakes into the 21st century.
 

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Got swing arm finished and painted with epoxy. And rebuilt the rear caliper.

The caliper was a mess. Looked like it had Dot 4 from 2000 in it. Had to soak it in solvent to soften the rubbers enough to get the pistons out, all 4 were write offs. But all good now, and no longer in stained bare aluminum.

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Back end is back togeather. Brake seems fine, good pedal. Shocks took a little jiggering to get the spacers sorted out, but ended up fitting well. Ne adjuster blocks were a pain, the swing arm had narrowed up at the slots. Took a big hammer to get the full sized blocks into the swing arm. I'll get the pipes back on and start in on the front next. Calipers, emulators and digital gauges.

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