Saturday, January 22, 2011

Doom, despair and agony on me.

Well, my fix for the Triumph broke a few months back. Misery.
For history, the shifter shaft was broken when I got the bike. It's a known design flaw in the Hinckley triples-there's a notch on the shaft to hold the shifter correctly, and the shifter itself is a piece of cast aluminum that you could club someone to death with. The result is: if you lay the bike down, even easy, on the left hand side, the shifter shaft will snap, rather than the shifter itself.
Now, on the newer triumphs, the shaft just slides out, and you can put a new one on with no problem. On the older ones, the part that engages the transmission is part of the shaft. To fix it by the book, you have to crack the case to replace it. Some enterprising fellows on the TriumphRat forums discovered that you could come up through the oil sump and replace it that way, with some creativity. Someone else figured out you could drill and tap the shaft lengthwise, and put a screw in to hold it together without opening anything. This is what I did, and then I dropped it (at like 2mph going over some gravel, I'm fine,) and broke off my fix.
What followed was a huge pain in the ass trying to do the easy fix again, which ended up costing me in time and money, almost as much as replacing the part. The plan was to drill out the old bolt, re-tap it, and put a new bolt in.

Problem #1: I got impatient when re-tapping the shaft, and broke off the tap in the hole. Taps are REALLY hardened steel, and it would in no way be drilled out (I tried. A lot.) I ended up using a dremel and multiple grinding bits to grind out the tap. It took forever, and two trips to the store to buy new grinding bits.

Problem #2: Here's a bad description of the fix: There's the shaft, which is drilled and tapped. Knurled spacers to replace the broken tip, and for the shifter to attach, and the bolt head, going through the spacers and attaching to the shaft, all held together with red loctite to keep anything from slipping. Like so:

SHAFT- SPACERS-BOLTHEAD

------- ------
| 000000 -)
=========== -)
| 000000 -)
------- ------


Result? The spacers ended up slipping just enough to make shifting impossible.

Problem #3: Stupid brute force fix attempt. I decided that JB weld would hold all that crap in place but good. I was wrong. The spacers still slipped, but now it was impossible to remove the bolt, so I ended up cutting off the bolt head, so now I had a shaft with about 3/4 inch of threaded stock sticking out of it. I found a local machinist to make me a big spacer to screw on to the thread, thinking that using the three individual spacers was my problem. I was wrong, although it held for about 15 minutes.

End of story? A few months down, and I've decided to suck it up, and replace the part coming up through the sump. More posts to follow.

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