Transmission Characteristics

[Tourville]

New to HONDA GL World - previously I built a BMW R100rs up from a '76 kitted R90, cam_carbs_Branch FlowMetrics Ported Heads, 3:08 gearing.

I remember my Spring Break run to DAYTONA BEACH on I-95 from Middletown,NY (under 20 hours with stops) somewhere around Georgia.
Rolling 85mph+ .. an open pipes burbling GL rolls past & disappears the distance as I'm down a gear looking for RPM
& feeling Parked.

This build is an '87 GL1200 engine//trans. & I'm wondering about Transmissions Cluster Choice - it's Cafe'.

The NY Hudson Valley - lots of hills .. mountains .. some highway.

At first glance, GL has three different transmission clusters:

GL 1000 relies on RPM to make speed vs 1200 with wide gear spread & cams cut for mid-range torque.

Between the 1000 & 1200 is there a best of both worlds transmission
with 1st four RPM gearing & a steep 5th Freeway Overdrive?

Will a 1000 trans cluster fit the R1200 case - with work?

Looks like a Great Forum -

Regards.

[redial]

keep smiling, although you have not got any responses. Very few of us have done anything with BMW, but good luck with your search.

[DenverWinger]

To clarify the question, he's a Beemer builder setting out on his first Goldwing project, I think he wants to adapt GL1000 gears into a GL1200 transmission for different ratios. To further complicate things there were some transmission changes between years of the same model. So more research into ratios.

I don't know that anybody here has gotten that technical with Goldwing transmissions, You'd have to spent a lot of time with calipers measuring shaft diameters, Gear widths, bearing locations and diameters, shift fork measurements etc. to see what would work.

Might have a little better luck on the NakedGoldWings site NGWClub.com (specializes in the 4 cyl 'wings) - They seem to like to do a lot of custom stuff there....

BTW - Tourville, Welcome to the forum! ...and don't even think for a split second that the above comments were meant to chase you off!!

[Tourville]

Thanks Mark - Clarification Accepted!

The BMW R series remains fun to build.

I met the Best back in the Days:

Udo Gietl & Todd Schuster
and all the crew at AMOL Precision in Dumont NJ.
who combined fielded the BMW Importer
Butler & Smith Inc. BMW DAYTONA Race Bikes
which led to the Battle of The Twins events.

2 cyl. bikes beating Kawasaki 4 cyl. at Daytona,
that was flat out incredible.

It's time for a Howl Build to get Fresh.

'85 - '86 LTD SE-i engine has captured
my imagination, not many intact available.

Thank You for the Great Greet Forum Good Will!


BMT

[ekvh]

Not sure what you’re after, but if it’s speed, the 84- 85 cams had more overlap, 20 vs 10 degrees. A commonly cited fact is the 1000’s had the largest cam lift and the most duration 235 degrees, ten degrees overlap. 1100’s were close but earlier closing times, less duration, the same overlap. Both had 38mm intake valves and 32 mm exhaust valves. A little known fact is that that the 1200, despite having significantly less cam lift, had almost the same intake valve lift and more exhaust valve lift due to different rocker arm ratios. They are hidden under the adjusters. It had 36mm intake valves and also 32 mm exhaust valves. It also has near maintenance free valves using hydraulic adjusters, different than automotive styles.

Transmissions can be swapped partially 1100 to 1000, but I don’t think the 1200’s will swap.

Gearing of the transmissions were very similar along the way. The first gear numbers switched and the fifth gear numbers switched a little, but you have to see them with changes to the secondary gearing and the final drive ratios. That’s where the money is.

Here’s a chart, it can be found at classicgoldwings.com but is layered a bit to get there. I’ll include a link. So trust me, 75-79 were all the same and 86-87 were the same as 85, but not 83-84. Scroll down to 1.708 which is your primary reduction, below that is secondary reduction which does flip/flop a little, then first through fifth gears, then final drive ratios.

The other variable is tire size, 1000’s were 17” with a 2.5” rim. The Lester rim for 1000’s was 16” and 18” both 3” rims. 1100’s were 17 inch 2.5” rims I. 80-81 and 16” 82-83 with 3” rim. 84-87 were 15”, with a 3” rim. You can easily adapt a 1500 final drive to a 1200 swingarm and have a 16” with a 3.5” rim.

It’s fairly easy to adapt an 1100 swingarm to a 1000 frame, adds 2–1/2” ?? of length.

Quick and easy drop-in swap is an 85-87 motor to a 75-79 frame, or to an 80-83 frame. You need to swap the output shaft to hook up to either a 1000 or 1100 because they use a circlip to hold the drive shaft on. You need to keep the black box ignition from the 1200. The 84 will go in an 1100 easily.

Either way you just lowered the gearing a bit, 2.83 to 3:1 in 1100 and a lot if you put it into the 1000, 2.83 to 3.4. That’s where it shines in the “Oldwings.” They really needed six gears to be a performance bike. (Can’t be done) Lowering the gearing gives up a little top end and mpg, but makes it responsive. Heck, it maybe doesn’t give up any top end.

The other mod in recent years has been to notch the pistons of a 1200 and put 1000 75-77 heads and cams on. 75-77 had more lift than 78-79. This gives it a bigger intake valve 38mm vs 36mm and bigger ports. 1.4” to 1.25” roughly. I’m not convinced it’s better. I had one for a couple years, went to the stock 85 heads and I think it’s better, but different. Doesn’t rev as high with power, but seems to make more torque down low. So shift sooner. With 1000 heads and cams it pulls hard above redline of the 1200.

I’m sure I’m forgetting things, but this is a brief run down of what’s been done. Too my knowledge, no one has dyno’d any results and only one has taken it to the strip and reported back. That was Oldboy, who put 1000 cams into an 1100, put the lowest first gear in and put a 3.7:1 gear in the final drive. He did a lot of work and barely made it in the high 12’s. Two drivers.

One other suggestion if you drop in the bigger motor is to change front ends. The 1000 was set up on string bean forks. Scary above 90 mph. All 1000/1100/1200 triple trees are interchangeable bearing wise. They bolt right in. Stops have to be altered. 1000’s have 37 mm forks, 1100’s have 39mm forks and 1200’s had 41mm forks. Dozens have adapted different forks to the bikes using AllBalls racing for bearings.

NGWClub is somewhat friendly to altering these bikes as is Classic and this site. You’ll always get asked why. The answer is always the same: because we can, and because we want to.

Here’s the link if my pic is fuzzy: http://filipi.com/wingdifferences.xls

If you still can’t see it, I can provide you with the steps to get there.

Good luck, take pics and share your progress. One thing you’ll find is these are MUCH cheaper than BMW’s.