Atila the Hun, 84 GL1200 disguised as a GL 1000

[backlander]

I read it somewhere but don't remember where, then again you can read anything nowadays. I also read they reshaped the fairings starting in 84 so they wouldn't provide so much lift at 80 mph and above, that front end still gets light at 100 mph on my 86. :shock: :smilie_happy: I remember I was treated to a wild almost tank slapper one day and I got to studying aerodynamics and what might cause it, I might have that bookmarked somewhere, I'll check.

 

[Steve83]

I'm still very skeptical of the front-end-wind-lift theory. I have no doubt that if I tried to lift the front of the bike by the fairing, it would break at the base before the front end would lift. Just my humble opinion...

 

[dan filipi]

Steve83 » Thu May 22, 2014 2:56 pm[/url]":32zjpmid]
I'm still very skeptical of the front-end-wind-lift theory. I have no doubt that if I tried to lift the front of the bike by the fairing, it would break at the base before the front end would lift. Just my humble opinion...

I'm with ya on that.
The weight is only 8 lbs at that.

 

[Denver]

Never understood why weight was used.Then again fairing on past 1100 was Vetter set up,on standard model.Are you sure about steering head bearings shape? That is most disturbing situation for front ends, if forks are in good shape with bushings, seals, & piston rings. Easy enough to fix,will make a tremendous improvement in way bike handles if they are worn at all.

 

[mcgovern61]

I thought the weight was for a front end harmonic issue with having the faring. I have (had) a Vetter faring and at 85 MPH I was getting the front end wobble going into wide sweeping turns on the highway. Of course, I don't think it is fair to blame the faring......the bike was loaded a bit heavy..... :hihihi: :doh: :yes:

 

[backlander]

I'm putting new steering head bearings in on this build and new handle bars. My original question was if I needed the handle bar end weights in the new bars since it will be using the Vetter 4 fairing. I believe more in the wheel/tire fork oscillation cause of the wobble, I just don't want any surprises popping up when I go to crank on this thing after it's built. The add-on fork brace for the early wings prior to 84 I think addressed the problem more so than the mass of weight attached to the fork. 84 forward already has fork brace built into them, but then again I survived a near tank slapper on an 86, so it makes you look into other areas for the cause. :headscratch:

 

[mcgovern61]

I have the fork brace on my '82. After my trip to Joe's and experiencing the high speed wobble, I researched it more and found out the bottom line was I overloaded the bike, I had too much weight in the back and the '82 Standard manual states to NOT ride an "accessory equipped" motorcycle over 80 MPH as the bike can become unstable.

 

[joedrum]

i had 1200 bars on the mongrel ..with the weights in the turn back on the handles was better and they were slightly taller made it perfect for hi way riding ...i never had extra weight on the front except the fairing ...at the time i knew nothing of weight for the forks ...there was times when wind was a factor but i dont think the wight was going to solve anything IMHO ...nonda did quit using the weight on 1200 right ...i think the build will be fine

 

[backlander]

:good: Thanks for all the input guys, why I love this site, so I'm going with no weighted handle bars, all info pro and con is always welcome and appreciated. That's the way we learn. :rocks:

 

[Steve83]

I'd wobble too if I was loaded like that!

 

[Steve83]

My theory on the weight: It's called an inertia weight because its inertia wants it to continue in a straight line, helping to prevent wobble. Try this: Take a 9-pound weight and hold it out 6 inches in front of you while you're riding in a car. Now, try shaking it side-to-side as fast as you can. Chances are, your body will twist more than the weight moves, and there's no way you'll shake it very quickly. It simply stablizes the forks. At 50+ MPH, the wind turbulance around the fairing wants to start oscillations in the front end, like a fluttering flag. Add some weights to the edge of that flag, and the fluttering is slowed substantially. Without a fairing, the bike pretty much slices through the air, and the Vetter fairing looks to be much more aerodynamic than the Hondaline, so much less fluttering. Just throwing out thoughts here - I should've paid more attention in those Physics classes!

Oops...way off topic...

 

[backlander]

Yeah, I think Gerry is in dire need of a trailer. :smilie_happy: I don't think it's off topic at all, imo, I ask a question that I'm facing with this particular build and it relates to how far do you go when retrofitting from an 84 to a 77 model. Over the years, so much was changed just for instance, frame design as they are different, trac suspension system, fork braces, fairings and weight of motorcycle was increased and to me all that and more takes into account when trying to build a safe and easy riding bike. Like I said, I want to hear all the opinions and theories pro and con then I could decide from all that info what might be the best solution.

On the build side, I am about half way through with tearing down the front end to work on the forks and rebuild the steering head, back to the shop for me, had to have a fresh cup of coffee. :wave:

 

[Steve83]

Enjoy the wrenching!

 

[Denver]

For what it's worth,1100 with 1200 front end,steering head to brakes, Aspencade if possible. Swing arm from 1200, with 1500 rear drive,& wheel set up is what i have planed for myself when i find an 1100 with title to transform. 1200 standards are hard to find,harder yet to afford. Answer, transform 1100. 80-82 have non- linked brakes, a plus for dirt & gravel roads.

 

[backlander]

Spent the afternoon wrenching on Atila, got the stem bearings and races out and the lower race was causing the problems, had several flat spots and surface was starting to fail.

Removed the carbs for refreshing

and spent about two hours trying to get four different "phillips" head screws out, they out to be outlawed. :head bang: So frustrating for something so simple. :Awe: I decided the motor is coming out so it's gonna be a while longer till I get to ride it. :smilie_happy: :mrgreen:

 

[dan filipi]

Agreed on the Phillips screws......with a passion!

 

[Ansimp]

I use an impact driver (screwdriver that you hit with a hammer) to undo any Phillips that is remotely tight. The trick is to make sure that the screwdriver bit is a nice fit as there are some really ordinary bits out there( the best in my opinion are the snap on ratcheting bits).

 

[joedrum]

always make or break decisions in this stage ...motor out ...sounds like you are really going to ck it out all you can now .... :fishin: :builder: :mrgreen:

 

[backlander]

Yeah joe, already had so much disconnected or removed just made more sense to take it back to the frame. I can then paint and polish the frame and engine up like new. Will make it easier to get that broke exhaust stud out of the head also. Made good progress for a old slow man today, got all the electrical removed, ignition, gas tank, final drive, swing arm and handle bar controls, rear shocks. Tomorrow I'll get the brake lines out of the way, center stand, side stand and hopefully lift the frame off the engine.

 

[Ansimp]

Great progress Mike( or is that "undress") :good: