Any tips on shifting this thing?!

AndyinCT · January 30, 2020, 06:25:50 AM

OK, so I'm not a total noob but this is my first coach with a manual transmission (5 speed). I'm a little embarrassed but I can't figure out the trick to not grind these gears. Sometimes I get it right and sometimes I don't.
I get the double clutch concept and I've had lots of manual transmission cars (synchro) but this is different.

When I release the clutch between shifts and put the transmission to neutral, I hit the throttle to raise the rpms and then push clutch in and move shift lever to next gear. Does this sound right? Do I need more rpms at higher wheel/vehicle speeds speeds? I drove this thing 900 miles back from Indiana but it was mostly just chugging along in top gear.
Any advice would be great.

Humbly,
Andy

buswarrior · January 30, 2020, 08:11:52 AM

Blipping the throttle on an upshift is exactly opposite to what you need.

Leave the throttle alone on an upshift.

The driver has to get the engine to approximate the rpm that the engine needs to be at for the gear you are going to.

So on an upshift, the engine will be slower for the next higher gear.

On a downshift, the engine has to be faster for the next lower gear.

Read RJ Long's shifting article at BNO:

http://busnut.com/forum/index.php/topic,3260.0.html

Happy coaching!
Buswarrior

dtcerrato · January 30, 2020, 08:15:52 AM

Only on a downshift do you raise the rpms during the double clutch neutral period. Raising the rpms "above" where its smooth to go into the desired gear then keeping just enough pressure on the shift rod for it to find the gear during the rpm drop has always worked better for our 4 speed crash box during a downshift.

TomC · January 30, 2020, 09:41:44 AM

Detroit 2 stroke engines fall off very quickly. Which means you have to shift quickly. But don't touch the accelerator on upshift. Takes timing and practice. Course the best solution is an Allison transmission (LOL)! Good Luck, TomC

Lee Bradley · January 30, 2020, 10:33:32 AM

Best method on a non-synchro is to not use the clutch at all, once you are moving.

richard5933 · January 30, 2020, 11:05:10 AM

Quote from: Lee Bradley on January 30, 2020, 10:33:32 AM
Best method on a non-synchro is to not use the clutch at all, once you are moving.

Not sure that this is correct. I've read that this can lead to excessive wear. Anyone have the facts on this?

luvrbus · January 30, 2020, 11:26:48 AM

His transmission being a late model probably has a clutch brake you push the clutch down to far and it will throw off the shifting big time.I never hurt a transmission shifting without a clutch once rolling a 13 speed Road Ranger would drive you nuts using the clutch for each shift

richard5933 · January 30, 2020, 11:32:03 AM

Quote from: luvrbus on January 30, 2020, 11:26:48 AM
His transmission being a late model probably has a clutch brake you push the clutch down to far and it will throw off the shifting big time.I never hurt a transmission shifting without a clutch once rolling a 13 speed Road Ranger would drive you nuts using the clutch for each shift

Some of the older models had clutch brakes as well - my '74 has one. Just like any heavy vehicle with a clutch brake, the pedal only needs to be depressed far enough to disengage the clutch plates on all shifts while moving, not all the way to the floor. Not only will that screw up shifting, it will ruin the clutch brake.

Fred Mc · January 30, 2020, 11:49:27 AM

Ive had LOTS of experience driving standards over the years and, in fact, still drive a manual shift Mini.
But I only drive the bus a few times a year and invariably have a little trouble(i.e. grind some gears)for the first 1/2 hour or so of driving. Most of my problem is double clutching on downshifts as it takes some practice to match the engine speed and trans speed. What happens is I have to attempt the shift once or twice.
The other thing is that when cold the trans shift a lot slower than when hot so you have to adjust to that..
My advice is to "know" the proper way to downshift and then drive it lots.
Where I live it takes a while to get to an open highway and the drive involves lots of stops and some fairly steep hills so by the time I get to an open stretch of highway Ive had enough "practice" that I get the shifts pretty well. In fact, one of the hills I climb I have to downshift from 3rd to 2nd in the middle of the hill which can be a little tricky as the bus is slowing down considerably due to the climb and if you don't get the shift properly it could spell trouble.
Anyway "practice makes perfect"

richard5933 · January 30, 2020, 12:03:30 PM

Not sure on the 5-speed, but on my 4-speed downshifts on an uphill must be started at about 5 mph faster than the desired shift speed. For example, I aim to downshift to 3rd when I get down to 45 mph. I start the downshift at 50 mph, and by the time I'm releasing the clutch pedal the final time I've slowed to about 45 mph.

The one thing that took a while to get used to is just how high the engine must be revved on a downshift. In a car, it's possible to just blip the throttle and downshift. In my GM 4108, I've got to floor the pedal for a second to get the engine speed near governor, and then do the downshift.

If I'm downshifting at a slower point in the curve I don't need to get the engine revved so high, so if I wait a minute and don't start the downshift until the engine starts to lug at about 40mph, I can shift into 3rd with less throttle. But, lugging the engine is not a good thing.

Also, timing on the downshift (and upshift) is key. Like Fred said, slower shifts when cold and faster when warmed up. If I try to put the trans in gear and it doesn't go easily, I let off the shift lever just a tad and try again. Forcing it doesn't usually help.

Last point, panic is a problem. Took me the longest time to get over that feeling of panic if I was having trouble getting the bus in gear. The more panicked you get, the harder it is to shift without grinding. It's hard to not panic when there is a lot of busy traffic all around and people starting to honk behind you, but they'll just have to wait a second or two.

DoubleEagle · January 30, 2020, 01:25:42 PM

Shifting without the clutch can be done quite well on Roadranger transmissions, but they are synchronized. As long as you avoid the clutch brake (if it works), it can be done on the Spicer going up, but doing going down is a little trickier. Read R. J. Long's article and every comment here, and then practice, practice. Sticking to higher gears will lug the engine and cause damage. If you hear light grinding, it will survive that, but if you try to force it and hear clunking, well, there goes a tooth bit. It is an art form shifting the Spicer, it is also a great anti-theft deterrent because the current generation probably won't get out of first.

I have the five speed in a 1982 Eagle that I drove through city traffic after it had been sitting for twelve years. The linkage was a little stiff, but it worked fine. You feel more connected to the bus with the manual, you can feel the vibrations and the forces down below. The only catch is your left leg gets a workout if you use it. The five speed is much handier to have than the four speed, so be thankful your bus came with it. The five speed is also wider than the four, and switching to an automatic or a Roadranger 10 speed would be easier space wise.

6805eagleguy · January 30, 2020, 05:12:41 PM

Quote from: DoubleEagle on January 30, 2020, 01:25:42 PM
It is an art form shifting the Spicer, it is also a great anti-theft deterrent because the current generation probably won't get out of first.

Hey!

chessie4905 · January 30, 2020, 05:45:32 PM

The current generation probably couldn't GET it into first.😋

AndyinCT · January 30, 2020, 06:19:13 PM

Well, I'm glad I asked!!
Very helpful information.

No wonder my downshifts were fine but my upshifts were not - I was raising the engine speed between upshifts!

I know I've got to practice but I tend to agree with many if you, there is a certain connectedness and satisfaction with driving this thing. I'm not sure its better than an automatic but it certainly is more engaging.

Now i have to look into this clutch brake thing. I have been pushing the clutch to the floor for all shifts. But, thinking back on it, there is a definite change in pedal feel about halfway through the stroke. Could that be what I'm feeling?

richard5933 · January 30, 2020, 06:22:11 PM

Quote from: AndyinCT on January 30, 2020, 06:19:13 PM
...Now i have to look into this clutch brake thing. I have been pushing the clutch to the floor for all shifts. But, thinking back on it, there is a definite change in pedal feel about halfway through the stroke. Could that be what I'm feeling?

There should be a small amount of free play at the top of the pedal travel. Then the pedal with disengage the clutch. Clutch brake should be the very last little bit of travel. On mine the pedal needs to be all the way to the floor. The semi I've been training in has a clutch brake which engages about 1/2" from floor. Can't feel the clutch brake in the pedal at all, but when it's not engaged it's really tough to get into first.