jacksinsomnia

I recently picked up a Miyata 914 (1990 I think from looking at the Catalogs) on craigslist really cheap. I didn't need a new bike, but couldn't pass up the deal. Now I need to decide if I want to keep it or pass it along to a friend. It has all the original Shimano RX 100 components, the only upgrade I could see was the wheels, not sure about the hubs.

I currently ride a Centurion Ironman Expert with all original Shimano 105 components. I'm pretty attatched to it, so unless the Miyata is a lot better I'll probably keep the Centurion (its that pink and yellow color that some people love and some people hate, I personally love it).
If I do keep the Centurion, can I switch the wheels and use the 7 speed freewheel/cassette (which is it, I always mix these up) from the Miyata with the 6 speed that is currently on the Centurion. Would the index shifting still work with the 105 derailer using the gears from the RX100 setup?

jacksinsomnia

bump. anyone?

due ruote 

You have a nice problem. Wish I could find a 914 too cheap to pass up. I guess a blind test wouldn't really be safe. But I'm wondering if you've done a serious test ride on the Miyata. They're both worthy bikes; you should trust your own sense of their road feel. Sorry, I'm a friction guy and can't answer the Q about indexing.

justinb

FWIW, my '89 914 has RX100 throughout, and it's got a freehub instead of a freewheel. You could still try it with the entire wheel, though.

Also, though this is an unfair comparison, my friends 52cm Ironman is a much lighter frame than my 56cm Miyata. I blame the splining, but it still rides sweet and I don't notice the weight on the road.

Someone more knowledgable will correct me, but I think the 105 derailleur should be fine with the 7 spd RX100 shifters.

Little Darwin

If you want 7 speed indexed, you need to swap wheels plus shifter, and everrything else should work.

All Shimano indexing derailleurs are pretty much the same except for early Dura-Ace (before 9 speed).

top506

The Ironman is a little sportier in terms of weight and geometry. The Miyata will be both stiffer and more relaxed.
There isn't a dime's worth of difference between RX-100 and 105 beneath the finish. The spacing between a Shimano 6-speed and 7-speed freewheel are different enough that you can't mix and match shifters, as I have learned the hard way.
I ride a 512, but would swap up to a 912 in a heartbeat, if just for the zoot factor. Maybe you should pass your sweet deal on to me. But I'd still keep my Ironman (in that lousy pink/yellow until I can get it painted)
Top

Ciufalon

I agree with jbonamici. Trust your feel and which one rides the way that feels best to you. I have both a Miyata 914 (I think a '90 or '91) with 105 components and an '88 Ironman master (white/purple fade) with 600 components. They are both great bikes, so if you are only going to keep one, just pick the one that feels best. Or keep them both and find another for your buddy. Enjoy!

miamijim

Shimano 6-speed indexing levers can be over shifted. When you in the last indexed position you can continue to pull the lever. Becase of this, alot of Shimano 6-speed levers can work on 7-speed systems. Back in the day we had guys running 7-speed indexed systems before Shimano did!!! Give it a try, it may work, it may not.

Comparison....

Weight: The difference has nothing to do with the spining. It has to do with the Miyatas overall tubing thickness. They used considerably thicker tubing than say, Reynolds, Colombus or Tange. I vividly remeber out cutaway frame being labeled 1.2mm for the thickest butt!!! J-Lo's butt aint that thick.

Quality: Miyata. No comparison.

Paint: Miyata..7 layers of paint and primer. 'nuff said.

Geometry: Miyata should be standard issue road race. No clue on the Centurion.

Ride quality: Because the Miyatas a heavier bike (just guessing) it will be a smoother ride while sacrificing a bit of zippiness.


That all being said...do you have geometry tables to compare the 2? Do you have weights to compare the 2?

Does the Miyata have an internaly routed rear brake cable? If it does are the holes gussetted?

Jim

Antipodes

Seven and eight speed compatibility is definitely not too much of an issue, but I'm curious as to how you managed to get 6/7 speed to work. I've tried this setup several times in the past with no luck - there was always too much cable pull and hence overshifting, usually by the time it gets to the third or fourth cog.

miamijim

I understand where your coming from but I honestly cant remember what we did. For some reason I want to say we did it with pre New Dura-Ace stuff with reconfiguring of the spacers. Maybe taking the older 7 speed cassette and converting it to 6-speed spacing then using it with the 6-speed lever......its been a long 25 years.