1982 GS1100GL Aero mods

[jkv357]

Originally Posted by Frank Lee

Fairing/no fairing/pulling a drag chute doesn't matter, your rpms are going to be the same at x speed.

Correct, unless you are altering the gearing.

The RPMs won't change, the difference (with improved aerodynamics) will be the smaller amount of throttle opening at the same speed.


Jay

[alvaro84]

And quicker acceleration and longer glides in the same range of speed

But a MT's rpms really won't change without re-gearing.

[RiderofBikes]

Originally Posted by Frank Lee

Fairing/no fairing/pulling a drag chute doesn't matter, your rpms are going to be the same at x speed.

I have a mechanical drive, analog Tach from the engine. It doesnt work so well. We measured engine speed with timing cover off(have electric ignition so timing adjustments weren't needed).
Much in the same case that my Speedo cable was thrashed when i got it, it would work now and then if the cable was connected right, but still mis-read loads. This bike was sitting for a couple years so most things like this were never maintained properly... Like the "factory" fish oil used for fork fluid... Was not a fun job!

Originally Posted by Christ

OP - Just a comment about the center stand thing - They're leveraged so that very little lift and a slight rearward attitude is all that's required to put a bike on a center stand.

If you didn't cut the brackets, you can often just "jack" the rear of the bike up and slide a pin/punch through the holes that retain the center stand to use it without keeping it installed.

Kept brackets on just encase when i sell the bike, IF someone wants it back to stock. I had to drive up on a curb or something, then prop stand down and effortlessly roll it back and presto. Ms shocks werent rebuilt at the time, so the bike sagged allot, requiring more effort to get the extra lift needed.
Had plans to turn into Cafe styled bike... then got side tracked from somewhere for other purposes. Haha, to think of it, turning this into a cafe bike is like a hippo with an eating disorder? Just doesnt work...

Originally Posted by bschloop

expanding foam works great for a plug if you want to make it out of fiberglass, and you will want more of a fixed fairing design like the windjammer fairings were. come to think of it, you might be able to find an old windjammer, and mod it using coroplast with pretty good results. they were made specifically to fit your bike which is a big plus.

I even thought about just leaving the fibreglass part out and just using straight foam, not the prettiest? but functional. I have around 30sq yd of fiber just laying around whats left from a blowout purchase from a guys previous subwoofer build. I kinda need a reason to give myself more work to use this stuff up. The windjammer idea has been tossed around, but there are crappy "used" overpriced ones for sale around my area and dont wanna plop down $$$ for a new one thats just gonna be modified.

Originally Posted by jkv357

Correct, unless you are altering the gearing.

The RPMs won't change, the difference (with improved aerodynamics) will be the smaller amount of throttle opening at the same speed.

Jay

While i totally get everyone saying about gearing related to speed


I beg to question with the mods i have done to my 2011 fiesta, I've been able to reach my 70mph rate with the engine only turning @~2900rpms then previously @3000rpms. 6sp A/T, with the system constantly matching engine to wheel speed(100% of tq to wheels at all-time)

I'm pretty sure (Throttle position = X amount rpm)
this is also a comparison to a FI and Carb setup?

[Christ]

Originally Posted by RiderofBikes

I have a mechanical drive, analog Tach from the engine. It doesnt work so well. We measured engine speed with timing cover off(have electric ignition so timing adjustments weren't needed).
Much in the same case that my Speedo cable was thrashed when i got it, it would work now and then if the cable was connected right, but still mis-read loads. This bike was sitting for a couple years so most things like this were never maintained properly... Like the "factory" fish oil used for fork fluid... Was not a fun job!



Kept brackets on just encase when i sell the bike, IF someone wants it back to stock. I had to drive up on a curb or something, then prop stand down and effortlessly roll it back and presto. Ms shocks werent rebuilt at the time, so the bike sagged allot, requiring more effort to get the extra lift needed.
Had plans to turn into Cafe styled bike... then got side tracked from somewhere for other purposes. Haha, to think of it, turning this into a cafe bike is like a hippo with an eating disorder? Just doesnt work...




I even thought about just leaving the fibreglass part out and just using straight foam, not the prettiest? but functional. I have around 30sq yd of fiber just laying around whats left from a blowout purchase from a guys previous subwoofer build. I kinda need a reason to give myself more work to use this stuff up. The windjammer idea has been tossed around, but there are crappy "used" overpriced ones for sale around my area and dont wanna plop down $$$ for a new one thats just gonna be modified.





While i totally get everyone saying about gearing related to speed


I beg to question with the mods i have done to my 2011 fiesta, I've been able to reach my 70mph rate with the engine only turning @~2900rpms then previously @3000rpms. 6sp A/T, with the system constantly matching engine to wheel speed(100% of tq to wheels at all-time)

I'm pretty sure (Throttle position = X amount rpm)
this is also a comparison to a FI and Carb setup?

Read my note about load and automatic transmissions. in theory, it shouldn't change the engine speed while under lockup, though.

[RiderofBikes]

Originally Posted by Christ

Read my note about load and automatic transmissions. in theory, it shouldn't change the engine speed while under lockup, though.

So... for ATs
Could it be that the AT/converter reaches a "lockup" state sooner, based on the effort needed by the engine to maintain a given speed?

Less load= less required power= lower rpm to do the same amount of work?
I know gearing and ratios are in there somewhere...

But then what is the correlation from an up-right riding position to tucking, and gaining anywhere between 1-5mph without changing throttle position with an MT? when were talking about stock gearing/ratios... i know it should be constant regardless... but this is not what im experiencing, im experiencing a gain in speed in this instance.

Maybe im just not getting IT

[FXSTi]

Originally Posted by Christ

Read my note about load and automatic transmissions. in theory, it shouldn't change the engine speed while under lockup, though.

His car has no torque converter. I do agree that rpm=road speed, the change is in load.

[Christ]

Originally Posted by RiderofBikes

So... for ATs
Could it be that the AT/converter reaches a "lockup" state sooner, based on the effort needed by the engine to maintain a given speed?

Less load= less required power= lower rpm to do the same amount of work?
I know gearing and ratios are in there somewhere...

But then what is the correlation from an up-right riding position to tucking, and gaining anywhere between 1-5mph without changing throttle position with an MT? when were talking about stock gearing/ratios... i know it should be constant regardless... but this is not what im experiencing, im experiencing a gain in speed in this instance.

Maybe im just not getting IT

Lockup puts the torque converter in a 1:1 state with the engine and gear train, so no, even if it locked up sooner, it would still maintain RPM/speed relationship.

I'm not sure about the details of his specific transmission. If it's an electronic CVT with 6 "speed" settings, that would definitely change it. I somehow doubt this is the case, but it's wholly possible.

I'd need to know more about his specific setup to know for sure why that happened.

The other option is that potentially higher load gave a false reading on the tach by 100 RPM, or that lower load is giving a reading 100RPM lower. Without a calibrated gauge, 100 RPM is sneezable.

[RiderofBikes]

Originally Posted by Christ

Lockup puts the torque converter in a 1:1 state with the engine and gear train, so no, even if it locked up sooner, it would still maintain RPM/speed relationship.

I'm not sure about the details of his specific transmission. If it's an electronic CVT with 6 "speed" settings, that would definitely change it. I somehow doubt this is the case, but it's wholly possible.

I'd need to know more about his specific setup to know for sure why that happened.

The other option is that potentially higher load gave a false reading on the tach by 100 RPM, or that lower load is giving a reading 100RPM lower. Without a calibrated gauge, 100 RPM is sneezable.

Thats what i was thinking, its not a CVT type... Green Car Congress: 6-Speed PowerShift automatic in Fiesta, Focus delivers a 10% fuel economy gain
^Just learned allot myself...
EDIT: would like to know where the 2.0l 160hp engine was an option... or better a diesel. lol

And the state of my current Tach on the bike is well ...less than desirable
I still need to do allot of rewiring, and replacing cables and such, maybe just find a digital read-out and rig it in some way.

[Christ]

Originally Posted by RiderofBikes

Thats what i was thinking, its not a CVT type... Green Car Congress: 6-Speed PowerShift automatic in Fiesta, Focus delivers a 10% fuel economy gain
^Just learned allot myself...
EDIT: would like to know where the 2.0l 160hp engine was an option... or better a diesel. lol

And the state of my current Tach on the bike is well ...less than desirable
I still need to do allot of rewiring, and replacing cables and such, maybe just find a digital read-out and rig it in some way.

Motomadness.com sells a nice unit, Bicycle computers can be used for both speed and RPM (to some extent). There are plenty of decent options for gauge kits.

[Frank Lee]

What the fork???

OP was talking about a bike. A particular bike. A bike with a 5 speed m/t. Not cars, not a/ts, not regearing. Not propeller slip on cargo ships either.

Unless it's been resolved and he's moving on now?