Frankenbike goes to the Darkside

Yamaha FJR Motorcycle Forum

Help Support Yamaha FJR Motorcycle Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
email just sent:

yeah, ya'll made the right decision - no question

just got home; left 1100 after breakfast, overcast skys, no precip, and sun came out in central MS...I was kinda warm riding through New Orleans to get to Metairie, my home suburb

Started out at 50 degrees and climbed 10+ slowly over trip home.

Course, we were putting distance from the cold front...Weather Channel at 9am showed brutal weather to our east drenching rest of FL

Look, we have to do this again...same deal would be fine...just advise when would be good...could meet in Panama City this time...stay in Navy facility near there. I need a TBS anyway...hay Walt...

I was just the trick for my first out of town trip since Francisteinbike is under me. I'm checking on gas mileage and it seems a little less than previous engine, but I'm not sure. I used to avoid at all costs gasohol, but now, at least 50% of pumps I pull up to...even name brand Shell, BP, Exxon, Chevron can be 10% mix which wasn't last year. I'm hoping to soon do a TBS (no equipment, maybe Jeff???), go to Iridium Plugs, and the chain on the AVCC needs adjustment (tightening) because of big time lag and forget to check it.

Great trip for me after weather worrys from us too - 512 miles.

Cheers,

Mike

---------------

BTW, either Walt is being extra polite to me or just old age memory loss: I think the only pic he took of my bike at the last gas stop at the beach in Navarre was my Air Horn. He grimaced to look at it and then asked me to blow it. His open rain suit jacket blew up to horizontal behind him and he gave a shit eating grin. "Oh, he mumbled." I responded, "that's only a 12volt blow...you ought to hear it when the engine is cruising along with 14volts available to it."

And he was a good sport as we decided to leave the Navy Air Museum and take a little ride. Along Pensacola Beach to the bridge going to the town of Navarre. Cummon Walt, it's on your way home. Well, Nick and I are one bar from reserve and the GPS after the Pensacola Beach bridge shows 30 miles. He's never gone near reserve on his ultra before and has no idea what his range is per the tripometer. About 10 miles from the bridge and 16-18 miles from the town, we both go on reserve. I know I'm good at the putterin' speed of 35mph on the beach road - Oh did I mention the howlin' wind and the "sand puddles" all over the road. Ziggin' and zaggin' for clean asphalt 4 inches wide among the sand. But hay, it made for an "interesting" ride. Convenient Store gas right near the bridge and all was well. Well, one pump with two sides, and three bikes. Took a bit of time.

I don't know...I was attracted to his ponytail last Jan, but that's OK.

 
It also came up during conversation, between weather checks and "Where's Vic?" that RH has been drinkin' coffee for quite a while. He couldn't quite remember if the 7AM was Central or Eastern, so he was there at 6. All by himself. Taking up a whole booth, and swilling the bean-brew.
Now we're officially wondering if we ought to be thinking about getting worried. It's after 8:00. I mean, is Vic lying dead in the motel room? Did he find a gurl person and went off someplace with her? Dunno.

What I'm worried about is discussing with the coroner how I knew this guy was dead in his room, but I've never met him, and being stuck in Chipley all week trying to 'splain that to the authorities.
Well, I had two thoughts.

First, he was calling around to replace his stolen clutch lever.

Second, he really was stretched out and stiff in his room.

"Excuse me, you are Vic's next of kin. I'm so sorry for your loss. Yes, he was meeting a number of his 'friends' like me who all ride motorcycles. I met him last April at our Southern FJR get together and we were both Navy. Yes, I'll miss him. BTW maam', the last thing Vic said to me was, "Yes, Mike, you can have my Feej!!!" " :rolleyes:

 
Nick was actually the reason for the trip, he was at the air station for a wreath-laying at his dad's grave there. The meet-and-eat for everybody else came from the fact that they were gonna be there why don't y'all come on up?
DSC_5526.jpg
4196853302_5ce0da2a51_b.jpg


 
Ok,

I'm Back!! :rolleyes: Sorry for the delay. Yesterday the weather here was so bad it knocked out my Internet Service all day. Then there were a few belated

birthday presents that needed to be unwrapped! :yahoo:

So, Let me start by giving my first impression of the 1,100 mile, 2 day, Vic & Howie's Excellent Adventure with the one and only RadioHowie!! <_< First off, He is WAY better looking in person (Thank God!!) than in those pictures of the resurrection of Frankenbike! Whoooa! :bad: He is a giant. I'd call it a cross between

Shaquille O'Neal and Sasquatch!! Except Shaq is WAY better looking and Sasquatch has WAY less hair! :eek:hno-smiley02: , But, he's a real nice guy. Funny too. More like Chewbacca!! :haha: Except Chewbacca has WAY less hair too! :D Ok, I'll stop here so I don't do too much damage to his :asshat: :asshat2: street cred.

Let's go to the ride. It was outstanding! Weather was perfect. As he stated, I was following him 80% of the way up there. 100% of the way back. The Darksider Tire looked sure footed the whole way. No sign of any torsion forses at all. It looked strong. On the straight stuff I was impressed with how true it stayed the whole way. No wiggle waggles at all. On the off ramps and changing lanes, even abruptly, I was blown away with how much real estate was making contact with the asphalt. I thought the smallish radius on a good lean was going to be problematic but, that wasn't the case. :clapping: He said the ride was nice and soft, and I believe it because it looked nice and soft.

Howie,

I gave the Modified Link a quick look see, and it looked like it would do the trick at the time, and it probably would. But, on the 6 hour solo flight home, (In the Freakin' rain!) I thought about it more and more, and the Aeronautical Engineering part of my brain started to give me a Teeny Tiny bit of heartburn. Almost like a little splinter in your finger that bugs the crap out of you and you can't stop thinking about it. So, my brain went into Structural Repair mode. I eventually worked something out in my brain that made the heartburn go away.

The guy/gal who designed that link at Yamaha had to do the math and come up with a specific Tension Load in Foot Pounds that the link would be under in a Hard Braking Situation. Having that number he/she then had to design the link to meet that expected load. He divided that number by two and made one lug on each side of the link that would mate with the one big attachment lug on the Swing Arm on top and the caliper on the bottom. You now have a half a link with half the load capability. In Airplanes or Motorcycles, That ain't the best position to be in!!

Here's the easy fix! Take the link out, get the other half and mate the two halves together on their flat surfaces and put them back on the outboard side like you already did. That way, You still have the clearence for your Darksider tire and you returned the link to it's original strength. WIN/WIN!!. After looking at my bike, I see you have plenty of clearence to the swing arm radius on the upper otbd side. If it's a little too close for your taste, you can grind the part of the link that's sticking out. No problem there cause all the structural strength is at the lugs.

Ok,

Now that all of that stuff is said and done, Let's get to the part about the possibility of finding a dead body in my hotel room with a girl, while she was infecting me with some kind of Chipley Pecker-Wrecker STD?!?! :haha: and the jealous boyfriend showed up! Although funny as hell! WTF?!?! :eek: You guys have been watching WAY too many C.S.I. episodes!

Here's the deal, (Minor Medical Issues first). After a lifetime of chronic ear infections. My left ear has enough scar tissue in it that I hear very little in that ear. Not deaf, just very little. My right ear is just fine. Add to that, I pinched a nerve real bad a long time ago at the base of my neck on my left shoulder. I can't sleep on my left side because even though it's all gone, I start getting a Hot shooting pain from hell within minutes. So, I always sleep on my right side. Unfortunately, That means having my good ear stuffed in a pillow. Then add a 9 hour bike ride, Tired as hell, hit to bed like a lead brick on the most comfortable hotel mattress I've had in years. All those little things together at one time, made this the perfect storm for being out like a light with wake up calls and people banging on my door and the police almost being called to use a battering ram to brake in to my room! Now, doesn't that sound like a perfectly good explanation? Does it? I think it does. So There!

In the interest of full disclosure, :unsure: You might want to add the 12 Tequila Shooters I had at the stroke of midnight to celebrate my Birthday!! :drinks:

Ok, maybe not 12 :unsure: I stopped couning after 3!! :unsure:

Don't Judge you BITCHES!! :drag: It was MY BIRTHDAY for Christ Sakes!! :yahoo:

All in All! It was one of the best birthdays ever! :yahoo: If you ever feel the need to make that Key West Run again. Let me know, I'm In!! You can crash at my place and we'll take off from here. I'm single and I have 5 bedrooms and 3 bathrooms. I only use one of them at a time! Just Sayin' :fuck:

 
Based on your aeronautical expertise, I will revisit the torque arm.

3 tequila shooters? Or 12. Doesn't matter. Pretty much the results Walter and I witnessed the next morning. :blum:

When you're ready to fly to the Land of the Pink Headband, just holler. I'm there! :yahoo:

[SIZE=8pt](shaquille? sasquatch? chewbacca!!??)[/SIZE]

 
[SIZE=8pt](shaquille? sasquatch? chewbacca!!??)[/SIZE]
They are all Gentle Giants! :rolleyes:

Even in folklore, I've never heard of Sasquatch hurting anybody! :D

The 3 day beard threw me for a loop! :huh:

God!..........I hope that WAS a 3 day beard! :eek:
Ummmm....I shaved at Denny's before we left. :D

And Chewie will rip your arms off if you don't let him win.

 
Last edited by a moderator:
Howie,
The guy/gal who designed that link at Yamaha had to do the math and come up with a specific Tension Load in Foot Pounds that the link would be under in a Hard Braking Situation. Having that number he/she then had to design the link to meet that expected load. He divided that number by two and made one lug on each side of the link that would mate with the one big attachment lug on the Swing Arm on top and the caliper on the bottom. You now have a half a link with half the load capability. In Airplanes or Motorcycles, That ain't the best position to be in!!

Here's the easy fix! Take the link out, get the other half and mate the two halves together on their flat surfaces and put them back on the outboard side like you already did. That way, You still have the clearence for your Darksider tire and you returned the link to it's original strength. WIN/WIN!!. After looking at my bike, I see you have plenty of clearence to the swing arm radius on the upper otbd side. If it's a little too close for your taste, you can grind the part of the link that's sticking out. No problem there cause all the structural strength is at the lugs.
I think the last sentence says it all, except you have it backwards. It should say: "all the structural weakness is at the lugs." They opted for a box section strut where the lug end is split to both sides of the tang it is being bolted to. Therefore, although putting both halves on the outboard side will work to increase the strength of the strut link, it will still not be as strong of a coupling joint because the tang will be loaded on one side only.

Looking at this picture:

Darkside13.jpg


It appears to me that the clearance issue is not really the brake link arm, but is actually the head of the bolt at the forward end. The clearance gained by halving the link is only the thickness of the material at the end of the link arm. How about just working on finding a shallower headed bolt instead and using the full (unsplit) link arm?

 
Looking at this picture:
It appears to me that the clearance issue is not really the brake link arm, but is actually the head of the bolt at the forward end. The clearance gained by halving the link is only the thickness of the material at the end of the link arm. How about just working on finding a shallower headed bolt instead and using the full (unsplit) link arm?
Fred, as usual, all good thinking on you part, but the picture as taken is misleading from a parallax point of view.

You have to remember that the torque arm, unlike as it appears in the picture, does not run parallel to the swingarm. The forward lug is above the swingarm and the trailing lug is below, so it only appears that the clearance-issue point is the forward bolt head.

HERE is where the clearance problem is with an unmoddified torque arm:

Darkside17.jpg


It's much closer to the trailing lug than the provided picture indicates since the torque arm is angling down from front to rear.

Imagine how it takes two referees to determine where a punt goes out of bounds in a football game. It takes two to triangulate where the ball crosses the sideline. You can't really tell where the torque arm "goes out of bounds" into the tire from just one picture. To really see where the contact would occur, you'd need a picture from directly above the torque arm and another from exactle 90 degrees to that view from behind or to the side the bike.

Darkside18.jpg


It's absolutely amazing how the first picture in this and your post clearly shows the front torque arm bolt as the potential point of interference. It is no where near the case.

Goddamn lying picture! Here's a side shot from the port side of the bike, through the swingarm. Obviously PLENTY of clearance at the forward mount:

Darkside19.jpg


Here's a "triangulation" picture, taken 90 degrees from the "above" shot. Again, the forward torque arm attachment point is clearly in front of the tire. The angled downward line represents the path the torque arm takes. The X is where the clearance issue occurs, where the torque arm would rub the area on the tire marked by the two red arrows:

Darkside20.jpg


So the clearance issue definitely NOT with the forward mounting bolt, but rather with the torque arm, about 1/3 of the the distance rearward from the front mount.

Hope this re-visitation clears things up a little.

And re-thinking the points majicmaker made with structural strength at the attachment points, I'm starting to feel like it's a tempest in a teapot. If, and that's a might big if, the rear brake was THE ONLY way to stop the bike, a stronger torque arm, as envisioned by the Yamaha engineers, would be called for, but in reality, rear braking is, what, 10% of stopping a bike? I really think it's a non-issue. The arm is an anti-rotation device for the rear caliper. That's all it is.

'Howie

 
Thanks Howie.

Sorry to make you go through all that explanation, just because I'm too lazy to go down in the garage and look at my own. My bad. But it sure did look that way in that picture... :rolleyes:

 
Pardon a dumb question, but I'm Irish so I'll go right ahead! RH, how expensive are "aftermarket torque arms" Eric refers to?
Don't know, Don. I procratinated too long to get one ordered in time for my North Florida ride. That's why I opted for my modified version.

Here's the link to Catfish's site Eric gave me. farklemasters.com.

 
I made this while you guys were discussing, so it's redundant now, but damn it, I made it, so here it is.

Animated GIF showing (about) the piece removed.

Darkside13.gif


 
Thanks Howie.
Sorry to make you go through all that explanation, just because I'm too lazy to go down in the garage and look at my own. My bad. But it sure did look that way in that picture... :rolleyes:
No problem at all, Fred. The subject deserved clarification and even I wasn't aware how misleading the original picture was until I shot from different angles.

Granted, I've only got about 1k miles on my Michelin, but so far, I can't see a negative in going Darkside.

I've probably got another couple thousand on my front Storm. When I replace it, i'm either going to go to a PR2-B, or I might....just might...consider finding rear-tire spec rubber in our 120/70ZR-17 size. But the PR2 choice makes more sense. :)

 
Pardon a dumb question, but I'm Irish so I'll go right ahead! RH, how expensive are "aftermarket torque arms" Eric refers to?
Don't know, Don. I procratinated too long to get one ordered in time for my North Florida ride. That's why I opted for my modified version.

Here's the link to Catfish's site Eric gave me. farklemasters.com.
IIRC, $30 for Stainless steel, $20 for mild steel, plus shipping. Expect around $7.50 for shipping due to weight and size.

EDIT - FWIW, ordering a foot of stainless steel online from the link in the Darkside FAQ costs about $12 shipped, (shipping being the same cost, the steel is cheap). For the non-drill press owners, Farklemasters is the way to go and a pretty good price.

 
Last edited by a moderator:
Thanks Howie.
Sorry to make you go through all that explanation, just because I'm too lazy to go down in the garage and look at my own. My bad. But it sure did look that way in that picture... :rolleyes:
No problem at all, Fred. The subject deserved clarification and even I wasn't aware how misleading the original picture was until I shot from different angles.

Granted, I've only got about 1k miles on my Michelin, but so far, I can't see a negative in going Darkside.

I've probably got another couple thousand on my front Storm. When I replace it, i'm either going to go to a PR2-B, or I might....just might...consider finding rear-tire spec rubber in our 120/70ZR-17 size. But the PR2 choice makes more sense. :)
Howie,

If you haven't tried the PR2's yet, You will not believe the milege you'll get out those things. You will love them! :yahoo:

 
...Animated GIF showing (about) the piece removed.

Darkside13.gif
Looking at wfooshee's animated GIF, it strikes me that if the torque arm is made single sided, even a "full width" one, when braking it will put a twisting moment on the mounting features at each end, instead of a simple pull. Might this lead to a stress fracture in time in the arm, the mounting lugs, or the bolts?

...If ... the rear brake was THE ONLY way to stop the bike, ...

...
It's not that it's the ONLY way to stop the bike. If it breaks while you are using the rear brake, the calipers will be violently moved round with the disk until the hydraulic line splits. I'm not sure what will happen then, but I can conceive of it jamming the wheel if it gets round far enough to reach the swing arm.

An attempt to calculate the force on the torque arm under heavy braking :graduated: :

Let's say

  • The rear wheel radius is 15.25 inches,
  • The effective brake disk radius is 5 inches,
  • Weight of bike and rider 850 lbs,
  • Assume a 1 G deceleration,
  • The rear brake providing 10%.
Then

  • Force on rear tyre is 10% of 850 = 85 lbs.
  • Force on torque arm is 15.25/5 x 85 = 259 lbs.
That's three quarters of RH's whole weight (from what I hear :rolleyes: ).

Imagine (most of) RH dangling from this one-sided fixing, the pull being repeated many times on the one-sided attachment points.

OK, I'm paid at work to look for worst case scenarios. It'll never happen :unsure: .

 

Latest posts

Top