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Clutchless shifting

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Bret Williams
(@bret)
Posts: 83
Estimable Member
Topic starter
 

Wondered about opinions on clutchless shifting. I have a 1984 R100RT and have put about 1000 miles on it. This is my first airhead. I have been riding 40 plus years mostly on Jap bikes with pressure lubed transmissions.

My airhead's clutchless shifts are smooth but not as smooth as a Jap bike. I have no missed shifts, nor do I do jackrabbit starts and acceleration. Over years of manual labor I have developed mild tendonitis in my wrists and prefer using the clutch as little as possible.

 
Posted : 03/05/2018 23:44
Richard W
(@wobbly)
Posts: 2590
Member
 

Wondered about opinions on clutchless shifting. I have a 1984 R100RT and have put about 1000 miles on it. This is my first airhead. I have been riding 40 plus years mostly on Jap bikes with pressure lubed transmissions.

The pressure-lubed gearbox has more to do with them running the gear set in engine oil instead of a true gear-rated oil. So that "feature" won't determine the types of shifting you are allowed or not allowed.

My airhead's clutchless shifts are smooth but not as smooth as a Jap bike. I have no missed shifts, nor do I do jackrabbit starts and acceleration. Over years of manual labor I have developed mild tendonitis in my wrists and prefer using the clutch as little as possible.

What you are seeing on the Jap machines is the much lower inertia of a lighter flywheel (typically only the weight of the alternator), aluminum clutch plates, and an aluminum clutch basket. This is becasue the Jap bikes were primarily designed to take the "sport machine" market away from the British. Any Jap touring bike offering was generally the same engine and frame with an added windscreen.

Compare that to the BMW, which in the 60's, 70's and 80's BMW was the top touring bike. Touring bikes need to be smooth and trouble-free, thus the large steel flywheel and rugged gearbox. No one expects a touring bike to shift fast; it's simply not a requirement. It wasn't until the late 80's and 90's that BMW tried to move into the "sport machine" market where they are today.

Therefore several thoughts come out of this...
β€’ Your comparison was between sport machine and touring machines. Apples and oranges, my friend.
β€’ Later model Airheads do have vastly improved shifting qualities, but your RT (a true touring machine) falls right at the end of BMW's reign as top touring machine.
β€’ I'm with 14724, if you're not getting an audible report from the gearbox, then keep doing what you're doing. You must be doing it right.
β€’ If you search these pages you'll find a similar complaint from me about the shifting on my 1979 RT being slow and clunky. I can only tell you to hang in there. The bike/rider harmony level tends to gel after 5000 miles, and one day you wake up with no gearbox complaints. In other words, you need to get used to each other.

Helpful hints...
β€’ Due to the large flywheel, it feels like you can ride around at 2200 RPM, but don't do it. You'll want to ride around with a minimum engine speed of ~3000 RPM. And 3000 RPM should become your minimum shift point. Added RPM really helps.
β€’ A change of gearbox oil REALLY helps. Once I changed g/b oil to a synthetic there was a dramatic improvement... which oddly enough took about 500 miles to manifest itself. No need to buy the $50 a quart stuff, you'll see the same difference with the $12/qt stuff from the local auto parts store. I'm using Valvoline 75/90.

Hope this helps.

Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.

 
Posted : 03/06/2018 13:42
Bret Williams
(@bret)
Posts: 83
Estimable Member
Topic starter
 

Thanks for the info guys. No more worries about transmission problems or wrist pain. Now it's just throttle elbow and I can live with that.

 
Posted : 03/06/2018 18:59
Lawrence Ayotte
(@8244)
Posts: 49
Eminent Member
 

I have heard that puttering around at too low rpm accelerates spline wear. Any insights?

 
Posted : 03/07/2018 06:12
Richard W
(@wobbly)
Posts: 2590
Member
 

No more worries about transmission problems or wrist pain. Now it's just throttle elbow and I can live with that.

Wrist, arm and hand pain could be caused by the ergonomics of your setup. I suffer from forearm pain from overused muscles as a result of too much engineering CAD work. So I take a lot of time getting my bars and levers just right. Then end by making sure my cables are lubed to reduce any "work" needed to operate the controls.

Some hints...
β€’ Sit upright in a very comfortable position on the seat. Extend your arms and the grips should be directly under your palms. On an RT with a fairly high screen you can afford to sit straight up, just like you would in front of the TV. (On an RS or S this can be slightly more forward leaning due to the lower windscreen.) You want zero pressure from body weight on the palms. Rotate the bars forward/back until that bar position is achieved.

β€’ I have never sat on a Corbin seat that allowed me to sit in what appeared to be the proper pocket for my butt cheeks. And I wear a 34" sleeve, which is about 2" longer than the normal 6 ft tall person. So you may have to sit further forward on a Corbin seat than what you might first assume to get the correct bar position discussed above.

β€’ Put your 4 fingers flat and straight-in-line with your forearm (as if to give a very classic, stiff, parade salute). While sitting on the bike with both palms lightly touching the grips, your 4 fingers in the "salute position" should be resting atop both levers. Rotate the levers on the bars until this position is achieved.

β€’ All Airhead models have a threaded hole to fit and use the throttle tension screw to relieve the right hand of holding the throttle open. Order and use: 32 72 1 230 874 "LOCKING BOLT" on the highway.

β€’ You want a handgrip with a barrel shape which more closely conforms to the shape of the loosely closed hand. This allows you to completely relax the hand while riding and simply "hang on" with the 8 fingers draped over the front of the bar/grip area. Formerly I used Gran Turisimo grips, but these days there are too many bad imposters out there. Recently I converted to a 7/8" grip made by Biltwell called the Renegade. They fit the BMW perfectly and feel wonderful. Find them on Amazon and Ebay for $16.

Photo: Renegade by Biltwell

β€’ Lastly, the angle of the 2 wrists has to be natural to be comfortable. Sometimes you pick a handlebar with a comfortable wrist angle, but by the time you rotate the bar back to meet your seat position, the correct angle has vanished. That's why these days all I use is 3-part adjustable handlebars off mid-80's Hondas. I get them from scrap yards for about $30 a pair.... or you can buy them from HeliBars for $600. Your choice. πŸ˜†

Photo: Honda 3-piece Bars

Before you can use these 22mm bars on an Airhead, you need to remove 20mm out of the center mounting section. I do that using a tubing cutter, then press in a solid steel bar inside for support, and finalize the job by welding it back together.

Photo: Shortened Bar Ready to Weld

With the 3-piece bars re-welded , re-painted and mounted, an infinite selection of angles is available between the 3 sections which allow my wrists and forearms to really relax. If the outboard sections are properly trimmed, they even work well within the confines of an RS fairing... which is saying a lot. Thanks, Honda !

Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.

 
Posted : 03/10/2018 21:25
Bret Williams
(@bret)
Posts: 83
Estimable Member
Topic starter
 

Thanks Wobbly. Have just worked up to one hour rides at 75 mph interstate speeds. Next move is ear plugs. Windshield moves the air to buffet helmet slightly, roar and whistle a lot. Previous owner cut down windshield four inches. Find myself crouching to deal with noise. May have to get full size.

From past experience putting on up to 1200 mile straight thru riding with the head bouncing around is no fun waking up the next day.

Corbin seat felt firm at first but it is wide enough to get leg support. After about a half hour it feels comfortable. Seems like the Corbin wants me to slide forward some.

Six inch extended forks should lift the front up enough to slide me back in the seat. Will have to do that, get the ear plugs, and do some 3-4 hour rides. Will adjust cable, bar, and levers per your suggestions.

By the way, just joking on the long forks. This ain't 1969 and I ain't Captain America.

 
Posted : 03/11/2018 01:40
Richard W
(@wobbly)
Posts: 2590
Member
 

By the way, just joking on the long forks. This ain't 1969 and I ain't Captain America.

That's OK, I'm not Jack Nicholson ! πŸ˜›

β€’ You need the correct height windscreen. I've been very happy with 2 screens from Clearview. Be sure and pay the slight extra fee for the "re-curved edge" which makes the shield direct air as if the shield was higher than it physically is. You want to look over the top of the shield, not through it, so you won't need their highest shield.

https://www.clearviewshields.com

β€’ Putting any kind of "edge protector" on the top edge of the windscreen breaks the air flow patterns coming off the windscreen and will reduce wind noise and head buffeting. At one time there was a company that sold a special shaped piece for $15/ft, but ANY shape will work. Here's some on Amazon

Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.

 
Posted : 03/11/2018 20:23

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