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Bantam Gearbox Woes

Featured Replies

I'm currently rebuilding a bantam D10a 4 speed engine and i've got a couple of problems....

1. The 3rd / 4th gear selector fork keeps popping out of engagement with its dog. I'm pretty sure that the selector fork is damaged but it doesn't look like there is any breakage. I have (hopefully) attached a few pics to help explain the problem.

Is the fork damaged or am I doing something else silly ?

2. I need to replace the bronze bushes in the final drive gear. Are there any hints or tips for this ?

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I am no bantam expert but all other dogs I have seen have 2 arms to keep them in place, looks like there could be one missing where the flat part is

is there anything that keeps it in place ,, cant see it been any good if it just flops about , as above you would expect 2 legs ,is it the correct selector ,did it have this problem before

  • Author

As you both say... I would also expect there to be 2 arms and I suspect that this is where the problem is but there is no indication that anything has broken off.

I bought the engine off ebay in a supposedly "ready to use" condition. Needles to say that when I stripped it I found the big and little ends were scrap as were the bearings. In addition, this sector fork was disengaged but there was no sign of any broken off parts.

  • Author

Indeed Totalshell. In-fact I have already seen that site but you can't quite see enough detail of the selector fork to tell if the one I have is damaged or not

both selector forks are the same so whip out the other and compare. personally i think one of the arms looks too short from my experience ,

getting bantam boxes together isnt straight forward but there are worse to work on.

Edited by totalshell

  • 2 weeks later...

Hi , looking at the photos , are you missing the selector fork roller's ??? .....

The cam plate rollers should hold the selector fork tight in the cam plate have you got these ?

The selectors are a pair so should have the same profile .

Looking at some spares I have they look pretty much the same as yours .

Maybe slightly more of a round profile on mine think yours may have been filed down ??

Hope this helps

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  • 2 weeks later...
  • Author

Finally found a replacement. Once it was in my hand it was very obvious that mine was damaged.

Next problem is the bolts that attach the cam plate assembly to the casing. Can anyone suggest anywhere I could get a replacement or have one they are willing to sell ?

Have you tried Chas field at Bantamspares.webs.com very helpfull carries new and secondhand spares don't forget locking tabs when you get bolts

  • Author

Just sent him off an email but he doesn't list them on his website

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