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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Pipe Dreamer on February 13, 2008, 05:24:15 PM

Title: 1970 and up 4905's
Post by: Pipe Dreamer on February 13, 2008, 05:24:15 PM
I was reading in Wickapedia that the 1970 and up 4905's have a syncromesh trans, no double clutching, is this a fact?
Title: Re: 1970 and up 4905's
Post by: Tenor on February 13, 2008, 05:29:33 PM
Only if you have an automatic!   ;D
Title: Re: 1970 and up 4905's
Post by: gmbusguy1 on February 13, 2008, 05:30:51 PM
No that is not true, all of the Gm's had non syncro Manual transmissions

Chris
Title: Re: 1970 and up 4905's
Post by: Pipe Dreamer on February 13, 2008, 06:04:26 PM
Thanks guys, this just goes to show you that everything in print is not true. I guess that i will have to work on developing a healthy left leg.
Title: Re: 1970 and up 4905's
Post by: JohnEd on February 13, 2008, 06:19:26 PM
There is an alternative.  Install an air clutch pedal with the valve in the coach under the pedal or near it.  That takes care of the HARD part.  Then install a small valve on the "exhaust" port.  The clutch will want to "slam" out and engage.  Close the "exhaust" valve till the clutch comes out smoothly and engages perfectly.  No more tired leg.  You can even rig the air to a button activated solenoid so you can keep the clutch engaged with your finger.  Let off and away you go.


I have been in a bus that had the fast idle activated with a switch so the gov controlled the engine speed closely and even on a hill the clutch engaged and "took" without stalling and the throttle wasn't touched.  This saved the clutch!  I think having both systems would be optimum.  Normally the fast idle cannot be used like this I am told and to modify it to do so was supposed to be dangerous.  Maybe, but if you aren't going to dump the clutch while in the building and are smart enuf in other situations it should be a real bonus.  I think to satisfy their reservations I would put a bright red light on the fast idle activation switch.  Wouldn't you think you could hear it running fast or see it on the tach?  Still, those that criticized this were VERY experienced and not to be ignored by anyone prudent out of hand.

I have done neither of these but this is what I have learned and I hope this helps you.

John