mel g said:I have an avanti escape hard tail with 26 wheels, also an apollo swift flat bar road bike and an argon 18 road bike. ...recently i find it harder to ride the avanti than my flat bar road bike or road bike.
That is a bit odd. Generally speaking MTBs have lower ratios but bigger steps in their gearing than road bikes.
I can think of two things:
1) It's the bigger steps between gears that is upsetting you and preventing you from finding the "right" cadence. Easy fix - slap on a road cassette, adjust chain length(shouldn't be absolutely required)
2) it's not about the gearing, but about the riding position somehow. Knee replacement surgery might well have messed up the geometry of your legs. Arm yourself with a spirit level, plumb line and a tape measure. Plot the distances between saddle, hand position and pedals for the "good" bike and the "bad" bike, see how they measure up. Also look at q-value(basically pedal-to-pedal width) between the bikes. If you use different shoes for the MTB and the road bikes, have a look at cleat alignment too. Odds are your Avanti has a higher Q value than your road bikes. If this is the culprit it's harder to address, but there are some options to get a narrower crank onto the MTB. Migh even be different crank lengts that are upsetting things.
mel g said:My question is can i swap my 700 flat road bike wheels (apollo swift), similar gearing setup, and use them on the avanti.
Yes/no/maybe. While 700 wheels usually will fit in a MTB frame, the brakes (if rim braked) won't reach. You can get a brake adapter(a horseshoe looking thingy) that bolts over the regular v-brake studs and let you set the brakes up for 700 wheels. They usually come with disclaimers about clearance limitations for which tires you can run. Then there's the issue with gearing compatibility. If you stay within the same number of speeds from the same manufacturer it's usually OK. Then there's compatibility WRT wear. Chain and cassette wear together. Parts that wer compatible out of the box might not be that after a few thousand miles.
mel g said:Can i just take the gear cluster from my 26" rear wheel and place on the 700 rear wheel
If the specs I'm looking at match your bikes, then it's no problem, they're both Shimano 8-speeds. But I thought is was the MTB you wanted to make more rideable? So why ask about what to stick on the flat bar road bike?
mel g said:...and then purchase two new wheels for my apollo.
Now it's getting confusing again. Which bike is it that you're trying to improve, and in which direction?
Getting a tighter span for the MTB is easy - slap on a road cassette. If the specs I found match what you've got it's no problem - any Shimano-compatible 8 speed cassette will do. (drivetrain wear excluded, better change the chain while you're at it)
Apart from losing a few really low gears this is a zero-consequence affair. Shortening the chain is neat but probably not required.
Sticking the road wheels in the MTB is IMO not worth it. Brakes have to be seriously modified for it to work, and the gain isn't much. Your highest gear will go up a bit, which is pretty much of zero use unless you regularly spin out as it is.
Getting a wider range for the flat bar road bike is also easy, slap on a 8-speed shimano compatible MTB cassette. You might need a long cage MTB derailer to go with that. Replace chain while you're at it.
In short: leave the wheels in the frames that they came in, and tweak gear ratios by getting new cassettes, or by switching the old ones around. Watch chain length and derailer capacity.
