Bicycle Tutor

I have a cheaper model road bike ( GMC Denali (KENT)) and I just had to replace the front wheel. I was riding and a dog ran in front of me so close to the front wheel that I could not stop and I am sure that you know the rest of that story. Bruised ribs, elbow cut and jammed pretty badly and front wheel bent beyond repair.
My son was able to get me a used wheel, an Aclass off of an Elleze and it is so much better than the original wheel that I could not believe the difference. This wheel will spin forever and is almost perfectly true. We had to convert from the old school axle that tightens on both sides to the quick release skewer type and it works great!
I have since wondered if I could convert the rear setup the same way. The bike has the twist grip shifter system, 3 speed front and 7 speed rear. I have found a used Shimano 105 hub and a 7 speed cassette, how much trouble to convert to this setup?
thanks james
By the way I just stumbled onto this site today and have already printed off the rear derailluer adj. tutorial. SUPER SITE!!

If you have 7 sped shimano shifters, you should be able to use any shimano 7 speed rear hub/cassette combination. Upgrading is always a tough business though. It is easy to get sucked in to spending quite a bit and spending a lot of time for small improvements in performance. Wheels make a big difference, but you'll still have the same brakes, shifters, etc. And improving everything often means spending more than just buying a better bike.
The 105 hub should work for your bike, but you would have to have it laced to your current rim or get a new rim and spokes. Lacing a wheel is probably a little beyond the beginner mechanic, though it is not that complex if you are adventurous. Unless it is damaged, your current wheel should be able to be trued to be nearly perfect as well. So if that is the big issue, I'd work on learning how to true wheels first.
Unfortunately, the best bang for your buck in upgrading is usually in the least "glamorous" parts. Getting better brake shoes, tires, and cables will often make a noticeable improvement in the bike without major expense. But if you locate parts and want to keep improving the bike, you will feel the difference.

Davem, thanks for the reply. I don't know much about this business, just hoping for some improvement in performance. When I got this new front wheel my average speed on a 20 mile ride jumped from 12.6 mph to almost 15 mph. I have only been riding for about 2 months with 25 miles being my longest ride to date.
I thought that if the upgrade on the front wheel made such an impact that upgrading to a better rear wheel might help even more. I can lift the rear of the bike and spin the crank and the rear wheel will free spin for a very short time. You can hear the hub clicking as the wheel slows almost immediately. So, I guess what I am asking is - would an upgrade to a 105 hub improve the bike's performance? And how feasible is this task?
You seem to suggest that I could stay with the twist grip shifter as long as I get a cassette and hub that is a 7 speed, correct? I assume that I would need a "new" wheel with the skewer type hub assembly?
By the way, I did upgrade the tires to Bontrager 700cX23, and they are great. I do not want to come across as a pest, I am just trying to get all of the help that I can for my old legs!
thanks James

15mph is a good average. It means you are generally riding around 17mph.
To increase any further then you may have to think about your riding position (aerodynamics) as much as about the bike?
It sounds like the old front wheel was causing some drag if it didn't spin freely.
The back wheel is a bit different as there is the ratchet of the freewheel (freehub) to contend with, causing a little bit of drag. (*only while freewheeling though, not when pedalling*)
If you want to check if the rear wheel spins freely then you will have to unship the chain from the cogs or remove the wheel from the bike.
As well, the 700x 23 tires may have helped to the increased average speed if you had bigger ones on before? Make sure the tyres are pumped up hard to near their stated max' pressure. (Purchase a track pump, with pressure gauge, if you haven't got one already.
To convert to the 105 hub it needs to have the same number of spoke holes as your existing one, if you want to re-use the same rim. Otherwise you will have to get a new rim.
Personally I wouldn't expect your speed to go up though just by fitting a new hub unless your old one is really worn out.

I rode 20 miles this afternoon(8/14), avg speed 15.7 mph ( 1hr 16 min 52 sec ), I am sure that I am getting stronger and that helps a lot, I am also sure that changing to the Bontrager 23"s instead of the 28"s helped a lot. The old tires had a tread pattern and the new ones are slick, so they probably create less friction.
I just thought that the cheaper components on the rear wheel being upgraded, might produce similar results. I figured a higher quality hub might spin more freely or accept the power transfer from the crank a little more efficiently. I had in mind something along the lines of Shimano 105.
I may just have to continue to get stronger and work on my technique. I am right at 6' tall and weigh around 235. I am 54 years old, so losing the weight is getting harder and harder. The extra inches around the waist make it hard to get down into the drops so I just grip the bars just behind the brake "horns".

17mph is said to be the point that air drag starts to be noticed on bicycles. I think you are right when you say it's you that is getting stronger. I am a bit? older than you but can do 10 miles in 26min.54sec's. (22mph).
I can only achieve this because I'm reasonably fit and use an aero position. The knees still catch the tum though.!! My last rides out on my "normal" bike (drop bar tourer )- but on top of the bars.
53 miles, average 15.06 mph.
47 miles, average 14.48 mph.
I have lost some weight this year and now weigh 170.lbs. This has made a significant difference to my hill climbing but not flat speed. By all means upgrade your bike when parts wear out but it's the engine that propels the bike. Keep at the "training", eat sensibly and the speeds will go up. (the pounds will drop off as well).
If you can do some decent rides, three times a week then I'm sure you will see some more improvement

If your wheel slows and stops rapidly, you might try overhauling the rear hub. It may just be dirty and/or out of adjustment. That said, a better wheel will work better, I just don't know how much change you'll see. I'd bet the tires made a bigger difference than the wheel. If you can find something compatible, I expect you can get a whole new wheel for not much more than what it would cost to buy a hub and have your wheel re-laced.

And don't forget that, as cyclerUK pointed out, at those speeds you start to benefit from a more "aero" wheel (deep section rims). They can be a bit heavier, but this does not matter on a flat course (once it reaches top speed, you do not have to accelerate the mass any more). You will also benefit from a more aero position, once the waist's circumference reduces and you can get down in the drops. Same effort + reduced drag = more speed. Tyres are basically "free speed", you have to buy new ones anyway from time to time, so just get a good set (you obviously just did that).
Bearing friction does matter, so overhaul your hubs once in a while and check the alignment. Check your wheels every couple of 1000km, earlier if you have bearings with simple seals and ride a lot in the rain. If the hub is shot, you should consider a new wheel (I replace my wheels, but I enjoy wheel building and work on a budget). I'd say, the hub's quality (assuming it is not a cheap entry level one) does matter less (so let's say Dura Ace vs. Ultegra vs. 105) than a correct alignment (and enough grease in the bearings).

Guys, I really appreciate your help. I am quite new to this whole thing and thanks to this site I know the difference in a bottom bracket and a hub. I don't know any more than enough to be dangerous to myself and my bike.
As far as the hub quality, it is the cheap bolt on style rear wheel (no skewer) and I am pretty sure that the hub is not even close to a 105.
I rode 20 miles again this morning and the wind was brutal on the return route. I tried leaning down into the "drops" and it definitely made me more aerodynamic. Yes, the old belly did get bumped some, but the real problem was that it seemed to put more stress on my knees. Normal? Is there something that I can do to help with this? Could the distance from the seat to the handlebars be too short or too long? I did manage to maintain 4 minute miles, but it was a real struggle.My son tells me that the " Wind is my Friend", but I sometimes think that he is evil!!!
thanks James

Knee pain can come from a lot of things (including that you were just pushing harder that day due to the headwind.) But seat position is usually a more critical issue than how far forward the bars are (which will have more impact on how your back/wrists feel).
If knee stuff comes up often, don't ignore it. Search for some proper bike fit guides online and find someone to help you check out your position. It's likely just your body adapting to your new workout. But knees take a lot longer to heal than to damage. So proceed carefully. We're not as young as we used to be...

Dave, thanks for the advice. I checked up on Exage and it is a Shimano product. I will start looking for brake components.
If I can ever get my old job back, due to economy many where I work have been "reassigned" to jobs at a much lower pay rate, I would rather spend a little more money and upgrade bikes. The bike I currently have is a little small for me and a better overall quality bike would be more fun. I would like to get maybe an older downtube shifter and slowly upgrade components.
thanks again for your help
James

Dave, Well the rear wheel made my decision for me this morning. My son and I headed out on what was supposed to be my longest ride ever, after less than 1 mile the rear hub came apart. The bearing literally fell out and the axle came loose from the hub. I guess I will be upgrading rear wheels now for sure.
James

Ouch. Had this last year with my Maillard Helicomatic hub (old road bike), 10km from home...
Get a decent entry level rear wheel (Shimano RS20, Mavic Aksium, Fulcrum Racing 7?, or comparable), the rear wheels should be about 70€ (online stores), a bit more at the local bike shop. The Mavic Aksium wheels (together with wheel sets from different manufacturers and in different price levels) were just tested in Tour, a German road bike magazine, basically they said "well made and robust, very good deal". I own them and cannot complain (ok, after only about 3000km, but still). The Shimano wheels sometimes had rims with irregular sidewalls, I don't know if they managed to get that right this year.
Of course, you can always get more expensive wheels, but I interpret the tests along the lines "more expensive - less weight - not as robust / long lasting (thinner side walls)". The hub quality might be better, though.
Good luck with your search!

I am looking at 2 or 3 rear wheels now, 1 has an 8 speed shimano cassette (used), would that work with my 7 speed? Could I just replace the cassette with a 7 speed cassette and a shim? Remember, I am on a very tight budget right now.
thanks James

7speed cassette + spacer should work. A used wheel is not a bad alternative when on a budget. I picked up mine from my local bike shop for about 10€ (8 GBP, 15 USD), complete with freewheel and two used tubulars... though I now completely rebuilt it. First a new rim (was tired of tubulars), 4 months later a new hub (the old freewheel broke, and the grooves for the removal tool where completely wrecked, so I had to destroy the hub to save the spokes (I'm upgrading the bike to 9speed cassette, but still with friction shifters, I'm working on a budget, too).
Oh, and don't throw away the old wheel, if the rim is still ok. You might start wheelbuilding one day (it is not difficult, you just need patience) and could just replace the hub. I don't see the sense in saving only the spokes, I build too few wheels and saving and organizing the spokes means a major hassle, with a high probability of never being able to reuse them.

Thanks joe.

Oh, and first thing you do with a "new" used hub: grease the bearings. It is not difficult and helps a lot. And make sure to get a high-ish level hub, my old exage hubs are shot, the 105 still work like a charm.