Thursday, February 18, 2021

Townie Update: Part 4

I used some Finish Line De-greaser to clean up the bearings
 The time finally came to get the head set cleaned and re-greased so I could button this project up for now and move on to other things. (I'll get to those in a minute here)

Recently I received some products from Finish Line to test and review for These were sent free of charge and this post is not being paid for or even a part of that review, other than to say this is how I got that stuff. (The review will happen and be posted on soon)  

The de-greaser is pretty volatile and very effective. I ended up spraying some on a rag and just using that to wipe down a lot of the parts of the head set which took the final veneer of varnished grease off. The head set bearings came out far better, and what tiny bits of goo were left were remnants of old grease that I wasn't too keen about chasing down. I could have made the bearing cages spotless, but I've already invested far too much time dinking around with this component already, so I cut bait and started reassembling the thing. 

That may rub some of your sensibilities wrong but this is a steel head set with about zero collectable value and as such it doesn't deserve more of my time, which is valuable. My aim is to make it function better than it would have, and that goal has been more than accomplished here. Your mileage may vary, but time doesn't grow on trees. Time to get 'er buttoned up! 

A closer look at that toothed spacer.

This is a pretty crude head set too. The adjustment is held by the interfacing of two toothed faces- one on the upper bearing race and the other by a spacer. Neither are machined with wrench flats, and since the adjustment can only be fine tuned to a tooth one way or another, wrench flats would be a waste. No, this is a hand adjusted head set. You get it 'close enough' and it's likely going to be a tic loose or a hair too tight. I cannot do anything beyond that as a mechanic. The design dictates the final outcome here. 

The top nut just keeps the teeth from skipping over each other and keeps the piece from rattling. That's about all it really does in this design. So, I hand tightened the unit after a thorough greasing with the Finish Line product I was sent to try. Interestingly, and maybe fittingly, it is a white grease, just like they would probably have used in the old barn at Trek back in the 70's. It also kind of feels like lithium grease. Anyway.....

I also used that grease on the threaded parts of the head set and the fork. This keeps things from hanging up and giving you a false sense that the head set is adjusted correctly. Dry threading parts together will often not allow you to get things fastened up completely, and you'll end up doing adjustments again, or you'll have parts come apart. Besides that, a thin layer of grease also helps to ward off corrosion. I was always taught that you should always have something on threaded parts of a bicycle- either grease or a thread locking agent. This bit of wisdom imparted to me early on in my career as a mechanic has served me well. With that thin coating of grease on threads, you'll also find that things thread together with much less effort. That's always nice! 

No machined slot in the fork threads, just a ground down area.

One thing I thought was odd here was that there was no key-way slot machined or cut into the fork's threaded section. This is typically done to match keyed one inch threaded head set spacers so they will not rotate when you adjust a head set. The Trek here has a ground down section on the threads instead. I have never come across this before.

It looks hand-filed, and this serves the same purpose as a slotted threaded section on a fork, it's just much cruder, in my opinion. Maybe that is how old-school hand-made forks were done, but it took me a bit by surprise. Just another example of how Trek was a completely different company in the beginnings of their history. 

So the rest of the job went without any fanfare. I got it all put back together and the apparent indexing was now absent, so I did take care of the problem. Plus I have insured smooth operation of the head set for a long time to come. Again, while it is a crude piece, it should be serviceable and ride okay. If I come across a nicer head set some day I may swap that in, but for now? I'm good. 

Now that this has been accomplished I am going to put the Trek townie aside for the time being and concentrate on a few other bikes. I have bits coming in which will need to be installed on bikes. I also need to service my gravel fleet as the day is coming that this sort of riding will commence again. Fenders will be fitted again in preparation for "Slop Season" and I may spruce up a 650B wheel set for soft conditions riding. Lots of maintenance will be happening. I'll have to investigate the possibilities of getting some 11 speed chains in here. I also have a couple wide range cassettes with light use available to me now courtesy of N.Y. Roll. So, going forward I should have anything I need to maintain these rigs throughout 2021, if I can snag some new chains.

So look for some maintenance posts coming in the next couple of weeks as I get ready to hit the country roads once again. 2021 riding season is just about here! I am pretty stoked! And the Trek> I'll come around back to that later, but it won't be forgotten, plus I have another commuter/errand rig I am going to be putting back into service here soon. Stay tuned for that and more!


fasteddy said...

The flat ground on the steerer tube wasn't so unusual in the day. Much more common on french steerers - both french threaded and french-origin tubesets (Vitus) as I recall. Some headsets had flats on the lockwasher specifically to engage with the flat on the steerer. The keyway was more effective for the headset adjustment, but was a sharp-edged stress riser and weak spot. Lot's of cracks started there when internal-expander stems were too high and over-tightened. Not that that didn't happen with the flat-ground steerers, too.

I don't recall specifically that Trek used these, but tubes were sometimes hard to get, so there was always something different when you built up the next one. Braze-ons varied a lot as I recall.

Guitar Ted said...

@fasteddy - Thanks for the insight. I don't remember this being the case on Italian steer tubes, but I didn't see a lot of those either. I do recall seeing split out steer tubes due to the slotted key way and over-tightening scenario you described. On braze-ons; The Vintage Trek sight has the scans of the original dealer brochures which indicate that a custom set of braze-ons could be ordered. Base price included the braze on stop for a down tube shifter band and the rear derailleur cable stop only. Anything else was an up-charge. My Trek has only the standard braze-ons. Since my Trek was the cheapest full-CrMo frame/fork available in early '78, that's not too surprising.