FlamsteadHill

I got my old Ross Gran Tour II out of "storage" yesterday. Put new tires/tubes on it, got the derailleurs adjusted, lubed the chain, new bar wrap, and took it for a 30 mile break-in session.

I pretty quickly noticed a "thump" from the rear wheel, concurrent with each revolution. Under pedaling you can feel it, and when free-wheeling you can actually hear the "ticking" of the freewheel get louder with the thump. At first I was thinking it was the wheel being out of round, but the increase in the sound of ticking makes me wonder if it's in the hub - bad bearing(s)?

It didn't seem to get any worse over the trip, but I did keep my speed to 20 or 25 in case something catastrophic happened. Had a few downhills that I could have hit 40 and that just seemed like an unnecessary risk...

BTW, pretty sure it's not a bad tire, because it also did it with the old tire(s). I aired them up - surprisingly they still held 90 PSI after a 20 year hiatus, and I took a short spin on it to decide of it was worth putting new ones on. Had the thump then too.

Bill Kapaun

Did you spin the rear wheel and look?

FlamsteadHill

Yes, but I don't know how to judge the severity, other than it doesn't seem to be much different than the front tire, or the tires on my other bike that runs smooth.

However, taking a closer look at things I did notice that as the wheel is free wheeling, the cog set is oscillating, as if the shaft is bent.

Six second video of hub:

FBinNY 

It sounds well within the range of normal. Likewise, freewheel wobble is normal.

In any case, a thump that you can feel is usually (almost always) related to an out of round wheel.

This could be the wheel itself, or simply a poorly mounted tire. Spin the wheel watching the tire with reference to a fixed point looking for high or low spots. If you find any, then spin the wheel slowly watching the reference line molded into the tire just above the rim. Check both sides, and if the reference line is uniform, spin the wheel checking the rim against a reference.

FlamsteadHill

Ok, watching the rim against the brake pad I can see that the rim has a wobble and a high spot in one location. Additionally, there is a loose spoke there, which makes sense. Maybe this is normal, but it would seem that tightening the loose spoke would actually make it worse - it's as if the spokes on the opposite side need to be tightened to straighten the wheel.

Is wheel straightening only for the well trained? I can sort of imagine the concept but I can see making it a whole lot worse rather than better...

cny-bikeman

If the spoke(s) on the side the rim is bent toward are loose that's an indication that the rim has been physically bent, and the only way to possibly save it is to carefully bend it back before attempting to true. That is best done by someone who is experienced with such repairs.
Are you sure it's a high spot?

Aubergine 

Do you mean the "bump" in the wheel is on the side opposite the loose spoke? If that is the case, you will need to tighten at least the loose spoke and the two spokes on either side of it. Try tightening the loose spoke until it has roughly the same tension as the spokes next to it, and then tighten the two opposing spokes each a quarter-turn at a time until things start to line up. Check also to see if the wheel is out-of-round while you do this. If it is, report back for more advice!

Wheel truing is not hard; it just takes patience.

FlamsteadHill

Well I got the wheel fairly "straight", but it is definitely out of round - has a distinct high spot. I'm guessing it's beyond me to fix it.

10 second video:

alcjphil

Notice that the OP mentioned new tires. My take would have been that the tires were not mounted properly, but that is just me

FBinNY 

That was a possibility which I mentioned earlier. However it's no longer on after watching the video which clearly shows a bent rim.

Odds are that sometime in it's prior life, this bike suffered an impact of the kind that can happen from a deep pothole, or hopping a curb.

A skilled and patient mechanic could probably get this wheel acceptably true, but that kind of mechanic is rare these days, and the cost of a new wheel low enough, that it makes more sense to start fresh.

Bill Kapaun

I think that rim is pretty much beyond anybody fixing it.

Richard8655

Had a similar bump recently. It turned out to be a faulty inner tube. On taking off the tire to inspect, the inner tube had formed a small bubble at one location that expanded into the tire, causing the thump at every rotation.

It was a new Specialized inner tube, and ever since used Schwalbe as much more reliable and durable.

FlamsteadHill

So how do I go about getting a new wheel? I have no idea what specs to look for other than 27".

Or is this a "take it to your LBS and let them handle it"?

i'm asking myself if this is a road I want to ride down. If I could find a used wheel for $10-20 and do it myself, ok. But I'm imagining its going to be an easy $100 at the LBS, and where does this end? On today's ride the crank started creaking (or maybe it was the pedals). Then what next?

This was more of an experiment to see if I wanted to get into a road bike. I think I've found the answer (yes!), and this bike will not be it, mostly because it is geared way too tall for my ability in most of the terrain I ride. But I thought if I could ride it the last month or two of the season it would help give me a good idea as to what I want and don't want in a new bike.

I guess if the wheel isn't going to just fall apart I'll probably keep riding it as is and dump it on Craigslist next spring for whatever I can get out of it

FBinNY 

You can buy a wheel online, but you need to know some details. obviously the rim/tire size, which can be read from the tire. Than the hub axle width, which you can measure directly, locknut fact to locknut face. Or you can measure the inside width of the rear dropouts.

Then there's the number of speeds on the freewheel.

So buying a wheel is easy, though the rim isn't likely to be an exact cosmetic match. However, you still need a special tool -- a freewheel remover which will cost $10-15. So you might end up having an easier time going through a local shop, which can remove and transfer the freewheel for you.

If you're thinking of a new bike anyway, you might put up with this wheel as long as it lasts or until you replace the bike.

While some here disagree, I believe (based on experience) that the wheel can be brought to a point of riding decently (nowhere close to perfect) so you can ride it with no or at least less noticeable thumping. The place to have that done at a reasonable cost would be a bike co-op, if there's one near you, or at an old school "dirty fingernails" bike shop. Explain that you don't want or expect a miracle, just get it decent so the thumping isn't this bad.

Aubergine 

I agree with FBinNY that your wheel can be rideable. What I would check for is your brakes- the brake pads must be adjusted so that they don't rub against the tire at any point of the rotation.

speedy25

In case there is any doubt- That rim is BENT. You wont ever make it true unless you disassemble the wheel and make the rim round again.

Flamstead- I do have a good wheel set about your vintage with 5 sp gears. PM if you strike out for a local replacement.

-SP

corrado33

We sell 27" rear wheels with aluminum rims for 20-30 bucks. (Rears are... rare (they're often the first to break), and the price reflects that.) Do yourself a favor and buy an aluminum rim version. (Steel rims are kinda awful.)

How would you go about fixing this wheel? If it were me, I'd try to fix it by tightening/loosening spokes first. If that didn't work or resulted in unsatisfactorily tensioned spokes, I'd go to more extreme methods. Basically I'd stand on the wheel and jump on the high spot to try to get it back into round. A bit of "percussive" maintenance. That is a relatively large bump though.

FBinNY 

While low spots may be actual bends in the rim, usually the result of an impact, high spots are almost always the result of spoke work, and rarely anything to do with the rim itself.

But we need to keep in mind that a rim is sort of like an arch bridge, and as you pill a high spot in, you have to give the "sides" room to spread. A common error of beginners s to try to pull the high spot in, without making room, causing outrageous local tension, and ultimately a weak wheel.

So, BEFORE trying to pull the high spot in, loosen the spokes to either side, then locate low areas which need to come up, and loosen spokes there accordingly. That will give the rim room to move and spread out equally.

Also, while everyone discusses tension, the real consideration is spoke length. It's the effective (stretched) spoke length that locates it's part of the rim in the right place, both radially and sideways. So, keep in mind that every full turn of a nipple relates to about 1/56" or about 0.5mm of radial movement either way. Sideways the multiplier is much greater, so you need to think in factions of turns.

Once you learn to think about the flow of rim material, and get a feel for response, aligning warped rims becomes much easier, and you'll be surprised at what can be brought back from the brink.

shelbyfv

It could be a build up of Slime in the tube.

FlamsteadHill

First, thanks to everyone else who had ideas or suggestions. I have a business that does a fair amount of shipping, so I know that unless I can get something local, shipping is going to cost as much or more than the actual wheel...

While I can see "simple" truing of a wheel is relatively basic (as I proved to myself with nothing more than a quick YouTube review and a half hour of tinkering), as I suspected, "roundness" is a LOT more complicated.

It really puzzles me that this is a "bump" and not a "dent". I can't imagine how it happened. I will accept that it might possibly be corrected by merely adjusting the tension of the spokes, because the movement of metal under stress/tension has always been a mystery to me. I would love to see a master fixing it. It would be worth the price just to see it.

FlamsteadHill

The thump was there with the old tires/tubes.

I bought brand new tires/tubes (tubes in the factory box) and installed them Saturday. I did not use any Slime. Thump still there. Slightly better after amateur straightening of wheel.

Did you watch the latest video?

I don't think it's Slime.

FBinNY 

Where in Vermont are you?

I know a number of skilled mechanics there and could refer you. Many would probably turn this away as a straight job, but some would take it as a skill challenge.

BTW - high spots like this don't happen naturally. They're usually the result of folks, who don't know better, tightening spokes elsewhere while truing, and pushing the rim outward where they didn't. It's like trying to compress a water balloon. If you push in one place, it bulges in another.

BTW - if you are willing to pay round trip postage to New York, I'll tinker with it for the cost of the two beers I'll drink while I do so. If I don't get it decent, I'll buy you the two beers.

FlamsteadHill

Eastern and mostly Southern, between Springfield and Putney or thereabouts. Not a whole lot of shops around here... Would definitely be interested.

shelbyfv

Sorry, misread the thread title....