deamers2010

Hey all. I'm new to the forum and the "serious" bicycle world. I owned a mountain bike when I was younger. A few years ago I was given a Univega Sportour; cleaned it up, new seat, handlebar tape, tires, etc.. then it sat for the past year or so while I ran instead of biking. Now I'm looking at using it to train for and use in a triathlon sprint.
I like the bicycle overall but do not like the downtube shifters or the friction shifting. I'd be minimally happy with moving the position of the shifters but ideally would like to change the type of shifter altogether. Any feedback on the possibility of this endeavor and direction of how to accomplish this for a newbie would be greatly appreciated. Below are what I understand to be the specs:
Suntour Cyclone M-II derailleur
mangalight fork HI-Tension stays
Suntour symmetric shifter pedals
Diacompe 400 brake system
serial number M339380

dabac

Can of worms...

Haven't got much experience with Suntour, but at a guess you'd need a new rear wheel, a new rear derailer and either bar end shifters indexed to match your wheel/cassette, or a set of brifters. And a bunch of small parts, cables, cable stops etc. A non-QS Campagnolo set of brifters would probably accept your front derailer quite happily, but Shimano parts are usually cheaper and easier to come by.

If the frame is a nice fit, consider picking up a donor bike and transfer parts from, or buy a bike in the desired configuration and sell that one on. Or keep it and put it on a trainer. Or keep it as your bad weather bike.

Do you really ride it with the saddle angled like that?

Phil_gretz

I like the bike a lot, and if it is your size, you have the right bike for starting out.

The brake cable housings have been cut too short, but if the calipers move freely and aren't sensitive to turn of the handlebars, so be it. If it were me, I would re-cable the brakes.

The saddle tilt adjustment needs work. Have an experienced friend assist you with height and angle.The saddle portion where your pelvis rests should be generally level. The present angle will cause your weight to fall forward onto your hands. You'll be engaging your arms and core just to continually "push" your balance point rearward, wasting energy at best.

As for the shifting setup... practice. Those derailleurs and shifters will work very well once you grow accustomed to the feel of the shifting and the combinations you'll need for your tri sprint. Give yourself 40 hours of serious training/riding, and you'll be proficient enough with the current shifters.

To update the shifting will cost some money. Generally, it's not cost effective to go this route. it's better to buy a different bike (used) that has the setup that you'd like. But here goes...

The other option would be to replace the freewheel, which I'm guessing is a Suntour 6-speed, but can't tell from the photo, with a modern 7-speed replacement (which will have uniform intra-cog spacing). The frame dropout-to-dropout inner spacing should accommodate your present hub with the new freewheel fitted. Have a local mechanic check it.

https://www.amazon.com/Shimano-MF-HG3...peed+freewheel

Then locate a set of Shimano 7-speed integrated brake/shifters like these:

https://www.amazon.com/Shimano-ST-A07.../dp/B007Q4MM1I

The shifter cable housings will need a "stop" on the downtube. You will have to locate a clamp-type stop or one that makes use of the threaded mount on your downtube (where the shifters are presently). I don't have a link handy for that.

That way, you'll fix the brake cabling problem and gain the efficiencies of on-handlebar shifting. Finally, you'll need a derailleur whose movement from the cable pull is matched to the spacing of the freewheel and the pull of the shifter. There's an A070 derailleur that would be a good match, but any Shimano will do .


https://www.amazon.com/Shimano-RD-A07...070+derailleur

I've used Amazon just for ease of illustration. Any bike shop can help you with this.
PG

wrk101

You are at the decision point. Doing anything serious as far as upgrading those shifters are expensive, as you will not only need new shifters, but those derailleurs will not index, freewheel will have to be replaced, etc. To add more speeds you are talking replacing the wheel and chain as well.

At that point, you are WAY ahead just selling the bike, and picking up a nice used one, set up like you want. For what you can get for your bike, plus what shifters cost, you should be able to find something. So what do you save? The cost of derailleurs, wheel, cassette, chain, and all the labor of course.

I love Suntour components, I have a pile of them. But they were made to work with different technology. Once you go integrated shifters (STI), costs get really high.

And finally, those top mounted DT Suntour shifters do not convert well to other technology. Basically, you will end up installing a cable stop ahead of them, and ignore the large shifter braze on. Looks pretty crappy at that point, but it can work.

Myself, I would convert to aero brake levers (less than $10 delivered on ebay), fix the cable routing issues, lever the saddle, and call it a day. Want more efficiency? Pick up some clipless pedals and shoes.

Want to finish a triathlon? It will work. Want to be competitive? Time for a different bike.

cycle_maven

There's a set of bullhorn handlebars and aerobars right now on my local craigslist for $25, with brake levers. That would get you most of the way there. A set of friction bar-end shifters would get you the rest of the way. Friction shifting is not bad with the new freewheels with shifting assistance; I'd recommend getting a new freewheel. So for about $100, you could have a very tri-worthy bike.

Want to be competitive? How many miles you ride is more important than the bike, unless you're at the elite level. When you start finishing in the top 10 of your age group, two things will happen- you'll know exactly what you want in a tri-bike, and you'll be ready to buy it. Until then, your bike isn't going to cost you more than about 1 or 2 seconds per kilometer.