Time to raise the rear a bit more

[carlson_mn]

Well, I have a Wilbers shock now and I love it. The bike doesn't bottom out like it did before in deep apexes but I still scrape bad. This last weekend I was following a great rider on a CBR1000RR and I continued to do a number to my Muzzy midpipe.

Oh, and this is the 'revised' midpipe that isn't supposed to hit. I purchased it in Feb 2010. Love the system and don't think it would hit before the pegs, but mine were already worn down a bit so the midpipe hits about the same time that the peg feeler does in its current state. I'm afraid it is close to wearing all the way through. Hope Muzzy can reproduce one if I need them to.

Right now my FJR is setup a bit higher than stock in the rear - no more than 1/2" but not sure. I'm going to give the adjustable Wilbers a spin or two to raise it maybe 1/3" more. I really don't like it raised up too much. I hang way off the bike to leverage it up as much as possible and still scrape. Not everyday but when I'm on the roads of choice me and the bike feel very comfortable, just not the midpipe

The left side wears real smoothly so I have no issues going to the left.

I also seem to scraping my original header mounting bracket?

Weird how it hits as the midpipe is tucked up as close to the bike as possible, it just should have been made with an angle at that point.

Just sharing my experience for anyone else who cares to know!

 

[Canadian FJR]

Those feelers are not worn very much, the issue is with the pipe. My feelers are pretty much gone and my stock pipe does not touch. My center stand, side stand and gear shift all touch but never the exhaust.

Canadian FJR

 

[exskibum]

Been there, done exactly that with the Muzzy pipe and Wilbers (with height adjustment). I installed my Wilbers in April 2005, and the Muzzy 4-2-1 in May 2007, taking care to install it as close to the frame and engine as possible. I then raised the rear in an effort to avoid the scraping. The problem was that I couldn't set the suspension high enough to avoid the scraping without getting a very undesirable hunting effect in the bike's steering when on the slab, going straight at any real speed. On the slab (which I avoid as much as possible), I don't want the damn thing darting for the next lane just because I turn to look at something, so I put it back to almost stock height.

I FINALLY cured the problem with the Muzzy collector and mid-pipe scraping in July 2010 with a ride-in to GP Suspension.

I had gotten the Wilbers on a group buy back in late '05 or early '06, telling them that I rode 2 up half the time, calculating my loaded weight high and noting that I rode aggressively in technical mountain terrain (hoping to get a stiff enough rear springing)**. At GP last July, Ben told me my Wilbers spring was rated to be 580 lbs, but tested at 542 lbs, and that I'd been bottoming it out from evidence on the top of the shock body. I watched Ben test it and got the step by step explanation of everything he was doing, what he saw and why he recommended certain things. In rebuilding and respringing my Wilbers shock, Ben and Dave settled on an 800 lb spring for my purposes (I'm 5'10", ~200 lbs, and ride 2 up a lot). Dave explained that the FJR just requires that much spring, and that it's common for many other shock suppliers to think a far softer spring will do the job, when it won't on this bike.

Here's what I'll tell you that I've said before: GP Suspension flat KNOWS their ****!!! I feared a butt jarring ride, but that's not what I got at all. I have never hit the Muzzy collector since, though I did scrape the right peg feeler, while two up, fully packed and leading the Wheaton Cluster feck down Skaggs Spring road at about 60 mph through advisory 30 mph marked corners about 10 or 11 days ago. Before GP fixed the problem with the Muzzy scraping, I couldn't get to that peg feeler in a corner, due to excess compression of the suspension causing the Muzzy collector and mid-pipe to touch down first.

IMO, you are not going to fix that Muzzy collector and mid-pipe dragging issue until you get that Wilbers sprung with a stiff enough spring to keep the bike's geometry from collapsing in corners under load. You can try raising the rear, but in my experience, the downside compromise of lost straight line stability is not worth it, and I'm not even sure that you can safely get it high enough to cure the problem in really hard right-handers anyway.

Good luck, though.

** FWIW, at about the same time, I was doing the same thing on my Blackbird on another group buy (also set up by Warchild) with Traxxion Dynamics in Georgia, so I was careful, precise and consistent in what I told each about the data that would affect my suspension requirements.

 

[wheatonFJR]

...I have never hit the Muzzy collector since, though I did scrape the right peg feeler, while two up, fully packed and leading the Wheaton Cluster feck down Skaggs Spring road at about 60 mph through advisory 30 mph marked corners about 10 or 11 days ago...

I was there and Rich was bookin'! I had to slow down after awhile because my front suspension was not dialed in...I was losing the feel of what the front tire was doing...it had a washed out feel to it, so I backed it off a touch for the rest of the way.

 

[carlson_mn]

thanks for the tips guys. And yes, the FJR does not like the rear lifted very much without it feeling very off on the freeway and just twitchy all around. I've got the Wilbers turned out a couple turns so maybe a half inch of thread showing - not sure where it sits compared to factory height, probably about 2/3" more and it is ok there. I've got it more dialed in now and I'm just gonna ride it! Not sure what pound spring it is - I got it 2nd hand but his specs are similar to yours, so it probably has a 580lb or so. 2 up it could really use more spring that's for sure but it's great solo.

I noticed that as I raised up the rear, a little less preload and a bit more rebound dampening really smoothed it out overall.

 

[rogdeb]

Adjustable links by Soupy

https://www.soupysperformance.com/catalog/item/4408900/4393129.htm

Good stuff, easy to adjust and worked well for me.

 

[weekend rider]

Try a bigger diameter tire like 190 instead of 180

 

[carlson_mn]

Adjustable links by Soupy

https://www.soupysperformance.com/catalog/item/4408900/4393129.htm

Good stuff, easy to adjust and worked well for me.

Nice units. My shock adjusts so I'm taken care of in the adjustability department. I like it about 2/3" up - still stable on highway but leans over a bit nicer.

Try a bigger diameter tire like 190 instead of 180

That's interesting - what's the theory on that?

 

[3dogs]

Try taking a Total Control class and learn to hang off more than you do.

Here is an FJR rider with his knee almost touching down--no scrapping. When his does drag his knee there is still no scrapping. The more of your body weight that is to the inside of the corner--the less lean angle the motorcycle needs for turning. This provides more traction as side-loading on the tires is minimized.

 

[charismaticmegafauna]

Try a bigger diameter tire like 190 instead of 180

That's interesting - what's the theory on that?

...learn to hang off more than you do. The more of your body weight that is to the inside of the corner--the less lean angle the motorcycle needs for turning. This provides more traction as side-loading on the tires is minimized.

Hmmm..., can you explain how that is? Or, is there (do you know of...) a link showing the geometry and force vectors of that?

On the old-days (before Kenny Roberts, Barry Sheene, etc.) road racers rarely, if ever, 'hung-off' -- they rode sitting on the saddle and leaned over pretty-far on skinny tires.

I think a diagram of the, respective, forces involved would be interesting to see... :huh:

 

[carlson_mn]

I do hang off the bike or at least sit and hang off the edge of the bike - it certainly helps.

 

[wheatonFJR]

Try taking a Total Control class and learn to hang off more than you do.

Here is an FJR rider with his knee almost touching down--no scrapping. When his does drag his knee there is still no scrapping. The more of your body weight that is to the inside of the corner--the less lean angle the motorcycle needs for turning. This provides more traction as side-loading on the tires is minimized.

I'd like to take that class in the Chicago area with my son some time...

 

[HotRodZilla]

I call BS on the hanging off theory, and believe the scraping pipe is a pipe and suspension issue.

I don't think people here really understand the theory behind hanging off, but the idea that it reduces lean angle and increases traction is a little off base I think. Decent suspension will have a greater effect on dragging issues than hanging off.

FWIW Carlson, my pegs are worn way farther down than yours are and I have never drug a pipe. I actually hit my brake lever at the Dragon a couple weeks ago, but that was a rear suspension issue that is soon to be remedied...Even with hitting the brake lever mount, I didn't touch a pipe.

 

[UselessPickles]

I don't think people here really understand the theory behind hanging off, but the idea that it reduces lean angle and increases traction is a little off base I think.

It all depends on what angle you are looking at. The angle between vertical and a line extending from the tire's contact point through the center of gravity will not change as you hang off the bike. What does change is that the center of gravity is no longer in-line with the bike and your body - it is somewhere in between. It's not the center of gravity of the bike that matters, but the center of gravity of the entire bike-rider system. When you hang off the bike, the bike will have smaller lean angle and your body will have a higher lean angle, but the entire bike-rider system will have the same lean angle. This allows you to corner at higher speeds without dragging parts of the bike on the road.

I can't comment on the claims of higher traction when hanging off. I could see that being either true or false, but it would involve some complex stuff about how the tire flexes/deforms at varying angles, possibly causing a larger contact patch when leaned less. There's nothing inherent about a smaller lean angle itself that gives you more traction, unless you're leaned over so far that it's a matter of whether you're leaning the bike beyond the limits of the tire unless you hang off.

 

[rogdeb]

Adjustable links by Soupy

https://www.soupysperformance.com/catalog/item/4408900/4393129.htm

Good stuff, easy to adjust and worked well for me.

Nice units. My shock adjusts so I'm taken care of in the adjustability department. I like it about 2/3" up - still stable on highway but leans over a bit nicer.

I have two way coverage then. Soupy's bones and fully adjustable Hyperpro suspension at rear.

 

[phroenips]

...learn to hang off more than you do. The more of your body weight that is to the inside of the corner--the less lean angle the motorcycle needs for turning. This provides more traction as side-loading on the tires is minimized.

Hmmm..., can you explain how that is? Or, is there (do you know of...) a link showing the geometry and force vectors of that?

On the old-days (before Kenny Roberts, Barry Sheene, etc.) road racers rarely, if ever, 'hung-off' -- they rode sitting on the saddle and leaned over pretty-far on skinny tires.

I think a diagram of the, respective, forces involved would be interesting to see... :huh:

I call BS on the hanging off theory, and believe the scraping pipe is a pipe and suspension issue.

I don't think people here really understand the theory behind hanging off, but the idea that it reduces lean angle and increases traction is a little off base I think. Decent suspension will have a greater effect on dragging issues than hanging off.

Read this: https://www.soundrider.com/archive/safety-skills/coming_unglued.htm

 

[bobg3723]

I do hang off the bike or at least sit and hang off the edge of the bike - it certainly helps.

Matt, there were times in the curves where I did witness you (and Tip) sitting square (or nearly so) in your seats leaned over to the point where it seemed a miracle there weren't sparks flying off your low side.

But moments after that vapor trails were all I could see as you pulled a Houdini Act down the pike!

 

[carlson_mn]

Right on Bob! - I'm heading to Canada fishing this weekend then we'll have to hang out for a ride and then grill something or whatnot to eat.

I agree with everyone there are both riding techniques and also suspension settings to minimize scrapping hard parts. I was just posting pics of the things I was hitting and I can follow up that raising the bike a smidge helped - raising it too much the FJR does not like. There's nothing that can prevent the muzzy midpipe from scraping - if you lean it over enough, it will scrape. It's in a different position than stock pipe obviously and does not tuck up away from the ground like stock does when leaned over. I noticed today my sidestand is also scrapped, made me laugh.

 

[bobg3723]

Bag some trophy eyes and pike up in Canuckistan der, Matt!! We'll explore some un-ridden twisties when you get back. PM me Tip's number and I'll see if he's interested in scouting some new twisty bits before he set's off for the Macon Dixon line.