B25 gear change

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B44Claus
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B25 gear change

Post by B44Claus » Thu Nov 14, 2019 1:19 pm

Hello!
I have a small gear change issue with my 69 B25 starfire. To engage 4th gear needs a quite firm foot. The same when shifting from 4th down to 3rd. It's not that is doesn't want to engage 4th gear or makes any strange noises, there is just more resistance to overcome. It appears that it shifts precise if I just apply the necessary pressure. All the other gears shifts with less effort.
Comparing with my B44 which also has a new cam plate spring the B25 feels tighter and in general needs a bit more lever pressure to change gear but it's only in 4th gear where it is noticeably more.
The engine and gearbox is freshly assembled with new bearings, seals & cam spring etc. The gearchange quadrant is refurbished with a new shaft with new splines.
Gearbox mainshaft and layshaft turns freely with normal resistance. If I mixed up the selector forks during assembly can it have the above described effect?

Brgds,
Claus
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Re: B25 gear change

Post by minetymenace » Thu Nov 14, 2019 3:09 pm

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Re: B25 gear change

Post by kommando » Thu Nov 14, 2019 3:46 pm

MM +1

Also make sure the camplate can move the full distance for fourth, I reversed a plate once for 1 up 3 down and 4th became hard to get into as the camplate was touching the stop too early, easy filing job to fix. Probably not an issue as in my case it was coupled with a too easy to get 3rd but as you are in there its worth a look.

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Re: B25 gear change

Post by B44Claus » Sun Nov 24, 2019 6:13 pm

Good afternoon,

Thanks Minety & Kommando for the advise and comments. I believe I did all the preparation & checking before assembly. Always hard to remember exactly as the motor was put together a year ago but not mounted in the frame until autumn. But I know I checked that the cam plate spring is fully home in the slot on the cam plate in all gears and that fourth gear is engaged before the cam plate hits the stop.
Actually it doesn't feel as if the gears are not selecting properly - in fact they engage with an audible "click".

In my original post I asked if misplacing the selector could have the mentioned effect? Or perhaps it would not shift at all then? By the way how do you tell which is which of the selector forks?

Last evening I was looking through my inventory of parts to get an overview of what was missing to complete a rebuild of a spare motor I have for the B44. Among the parts are a couple of new cam plate springs I bought from two different suppliers:
Spring1.JPG
Spring 2.JPG
If you look closely they are not identical. The left one has a a sharper bend where the blade meets the end with the peak. The right one is more curved in the same location but the peak that engages with the cam plate is more pointed. I could imagine that the right spring with the more pointed end/peak is more difficult to move out of the notch once it's engaged. Perhaps this is the situation I have if I installed one of these?
Can you tell if any of the springs are wrong?

Brgds,
Claus
B44Claus

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