| Author | Message | ||
| Bob Wies (Ncbob)
Rating: N/A |
Here's a question for you old timer non-sync tranny drivers: With a properly adjusted Twin Disc type clutch and a non-sync transmission I've hear (maybe a fairy tale) that a quarter (or half clutching) pause before pushing the pedal back to the floor to complete the double-clutching will have a real effect on slowing down the transmission input shaft to the idle speed of the engine before shifting to the next higher gear. Might there be any truth in that tale? Inquiring minds want to know...... NCbob | ||
| R.J.(Bob) Evans (Bobofthenorth)
Rating: N/A |
I must be missing something in your question. Why do you want to slow the input shaft to idle speed? On my 10 spd RR I've got about a 350 RPM drop. Unless I'm shifting at really low RPMs (like 1200) I have to hold the engine speed up in order to make the shift. I generally skip shift unless I'm pulling a grade so I have a larger RPM drop to work with. I suppose on a 4 spd you may need to drop to idle - never drove one so I can't comment. | ||
| Ron Walker (Prevost82)
Rating: N/A |
If you push the clutch to the floor while double-clutching, you will burn up the cluch brake. Ron | ||
| Bob Wies (Ncbob)
Rating: N/A |
OK Ron, please expand on that a bit for this 'newbie'. I'm about to replace the clutch in my MC5A and don't want to burn anything up on the trip back home. I, and possibly others, would appreciate it if you would go through the shifting procedures of a twin disk clutch with us. I happen to be using the Spicer 4 speed. NCbob | ||
| Ron Walker (Prevost82)
Rating: N/A |
To double-clutch, when shifting between gears, you only push the clutch half way down. When you are in neutral and a stop light or WHY, and want to put it into gear without grinding, you push the clutch all the way down and it will enguage the clutch brake and the front input shaft of the trany will stop rotating and go into gear. Ron | ||
| Stan Rating: N/A |
I think clutch brakes were pretty rare in these vintage buses. I heard of them in Eagles but not in the other common makes. | ||
| Bob Wies (Ncbob)
Rating: N/A |
Well, today I had the opportunity to speak with and OTR trucker (locally) who hauls a tanker filled with H2O (water for those of you from Rio Linda). That's heavier than Gasoline or Diesel Fuel...by almost a lb! In a 9600 Gallon tanker @ 9# per gallon that's a whopping 43+ tons (86,300 lbs. for those of you from Rio Linda). That's one HELLUVA load! Here's the point. Even though he's punching a 13 speed R/R he tells me that "half clutching" through the shift and "feeling" the stick ready to go into the next gear has worked for him for almost 25 years. The point being...that the "half clutch" gives the clutch brake a chance to slow down the input shaft of the transmission and allows enough release to make the shift. It's not quite like "slick shifting"...but almost....and saves the clutch brake. Remember now, that I'm a 'newbie' and I'm only asking for and receiving info about clutches. FWIW NCbob | ||
| Bob Wies (Ncbob)
Rating: N/A |
Thanks Ron, I was out when you message was posted. Sounds like we're in general agreement, huh? Thank for you input. NCbob | ||
| john w. roan (Chessie4905)
Rating: N/A |
4905's have clutch brakes. | ||
| Ron Walker (Prevost82)
Rating: N/A |
ehhh. Ron | ||
| convertedbird Rating: N/A |
deep clutch with a clutch-brake and you are trying to stop the whole bus, half clutch and you will never slow anything down with the clutch- brake. put couple of clutchs in 4106's and they had no place for one. Jim | ||
| Gary Stadler (Boogiethecat)
Rating: N/A |
The whole reason for a clutch brake is to stop the transmission's input shaft from spinninng when you're sitting at a stop in neutral and trying to put the tranny in gear. In that situation you press the clutch all the way to the floor and if everything's adjusted right, the clutch brake will stop the tranny from spinning and allow you to engage gears without grinding. Once you're moving, you should never press the clutch all the way, because you don't want to engage the clutch brake at that point. That's when half-clutching is the way to do it...if you need to clutch at all. After a while (it took 5,000 miles for me) you'll get better and better at watching the tach and speedo, and shifting without using the clutch at all. But that won't come overnight...  | ||
| john w. roan (Chessie4905)
Rating: N/A |
Actually..the 4905 has a countershaft brake, not a clutch brake. Mounts at end of transmission countershaft behind a removeable cover.Consists of three small discs.Don't know if they had this on 4106 as I don't have the manual. |