Source for New Tach

[spub]

The "L" or 90 degree drive on my mechanical tach gave up the ghost last ride. My bike is a 3 1/2 Sport, but a mechanical tach was added later.

Does anyone have a source either for the "L" drive, or an electronic tach, in the event this is my only option?

Thanks.

[3potjohn]

Do you mean the drive gear on the rear of the tacho? Mine packed in the other day,It seems to have a crack in the black gear housing.I removed it and found a couple of ?nylon gears, one looking a bit worn out at the end that rotates in the back of the gear housing.I've glued the thing back together and evosticked it to the tacho. It works but what a palaver

[spub]

No, I am talking about the 90 degree drive that screws on to the ignition cover for all mechanical tachs (the electronic ones have the simple plate). Have found a source for one that might work, but I was hoping there was a stash of old metal ones around (the new ones have nylon bodies). NLM has none.

[spub]

Was able to obtain a used 90- degree tach drive. From taking apart the old one, it appeared to me the internal gearing is fairly robust, there is just no simple way to refresh the grease since all parts are press fitted it. I have seen other similar drives with grease gun fittings, so I drilled some holes in the old unit to see where a grease fitting could be attached. Best place appeared to be the top of of the unit. This allowed for more material for the grease gun fitting to screw into (as opposed to being screwed into the end of top cylinder of the unit), and had clearance so allow grease to flow onto the top gear. Problem was, there is not enough material to screw in the fitting and keep it secure so it would not pull out when removing the grease gun tip from the fitting (and you know how I figured this out). Learning from the old unit, I drilled a 7/32 inch hole in the top of the new unit I obtained, and used a rubber grommet to cover the hole. I use a rubber tipped grease gun fitting to seal the hole and squirt grease. This, hopefully, will extend the life of the unit for as long as I own the bike, since NO ONE (excepting Andyroach) had a replacement drive, used or new.

It also appears that you have to be very careful in spacing the drive from the bit which engages it that is mounted on the end of the crankshaft. This spacing is controlled by shims/spacers inserted between the unit and the cover onto which the unit is bolted. When you purchase a new pick up from NLM they give you a spacer to use to correct the spacing, since the new pick up move the bit on the crankshaft a bit further outward. The spacing should be fine tuned with shims. This can be easily done by attaching the cover with the two mounting screws without the angle drive attached, and then inserting the drive through the mounting hole on the end of the cover and engaging it on the bit on the end of the crankshaft. The distance bewteen the unit and the cover is a two or three hairs more than the amount that needs to be taken up by spacers/shims.

Will try to take some pix and post. The scarcity of these drives has lead me to be very careful about the installation and maintenace of these units.

[morini500dave]

Hi all.
I've seen right angle drives on some older Guzzis and later Meridian Triumphs as both have Veglia speedo/tachos but at the instrument end,don't know if one could be modified

Dave.