1976 T140V Tachometer Drive Cap

[ZILCH]

Hi Folks,

I just picked up a 1976 Bonnie 750. I have been doing an assement of the bike and notice the tach drive was covered in duct tape. Further examination revealed the cap covering the small worm gear that drives the tach cable is missing. I checked the rest of the tach system and it works fine. The cap keeps the small worm gear in place and seals that part of the housing.

I have located a whole drive for $79 but I just need a cap. Does anyone have a good source to get a cap?

Thanks,

Zilch

 

[The Seeker]

Wow....I know the cap you mean and I believe older and newer models would have the same exact drive (and thus the same cap), but I just don't think they come separately. Maybe if you bought an older used drive, you could scavenge that part only???

 

[ZILCH]

I have found a way to repair the missing cap. I'll try it out and report the results here.

 

[DaveM]

Yes please let us know as I am interested to see how this can be done

 

[ZILCH]

Here is the link to the method to be used. I will see how it goes.

http://books.google.com/books?id=IQ...m=6&sqi=2&ved=0CGAQ6AEwBQ#v=onepage&q&f=false

 

[The Seeker]

......and it only costs a nickel!

 

[Rocky]

That's pretty clever

 

[ZILCH]

Ok well it worked. The material cost 5 + 1 penny. The time that's another matter. The seating area in the housing for the cap was not deep enough to allow the nickel to be seated and the housing could be stake to hold the new cap on. I used jewlers files to tapper the edge of th coin and trim the diameter for a better fit. The tapper allowed the housing edge to be peened over to ensure the cap is secured in place. I did not have a .250" bearing handy so I tried a bicycle bearing which was .200 or less diameter. However there was not enough clearance to allow the new cap to seat properly. The parts book called out a rub washer instead of a bearing so I used a penny greased up on each side. One word of caution be sure to install the L/H threaded nut in the housing before putting in the driven gear and new cap on.

I finally got the bike's battery to take a charge after it sat for two years in the bike and since the last start by using the epsom salt method. The first time I tried it would not even take a charge from the charger and was totally dead. It is charging now and should be finished tonight. I will fire up the bike for the first time since I got it.

 

[DaveM]

Good going on this mod very clever idea indeed

 

[grandpaul]

An old trick worth every penny.

 

[Gromit]

Ummmmmmmmmmmm, what's a 'tachometer', where will I see it and why does it have a 'cap'??:y11: Can't you just plug it shut with duct-tape?

 

[CarlS]

Thanks for the link. I learned something.

 

[ZILCH]

By the way after several failed start attempts I pulled the caburator bowls, and adjusting screws and clean up the old gas gunk. She fired up after the thrid kick. It was nice to hear the Bonnie running for the first time. Now onto rebuilding the front master cylinder ; )

 

[CarlS]

Very good. Congratulations!

 

[grandpaul]

It's great when they come back to life after a long sleep!