mega gear question.

[toker_ace]

Does a mega gear freewheel require a special derailler? I'm having problems with my derailler on a mega gear freewheel i put on. thanks

[Electricycle]

The nature of Mega Range is that it has a very broad ("mega") series of sprockets, in terms of the number of teeth on each. You might have a range from a 13 tooth to as much as 32 or maybe 34 on the largest sprocket.
This means than when shifting through the range from large to small a lot of chain becomes slack. This is why you need a rear derailer with enough travel to take up and release all that slack chain.
So the answer is YES, you need a compatible der. You also need to cover the correct number of sprockets or your indexing won't work smoothly.

[Elmo]

You need a wide range derailer. I have a 8 cog megarange cassett on my pedal recumbent and it works flawlessy. I do not have index shifting I use barend shifters. For me they work much better than index. Maybe because I have a very long chain, 2 1/2 regular chains. My bike is a toureasy clone. Here is a link to harris cyclery with info and a range of derailers from expensive to cheap. Campagnolo, Shimano and SRAM Bicycle Rear Derailers from Harris Cyclery I woyldn't mess with the lowend ones, get the best you can afford, you will be glad you did in the long run. Hope this helps.
Elmo

[Blakenstein]

Originally Posted by toker_ace

Does a mega gear freewheel require a special derailler? I'm having problems with my derailler on a mega gear freewheel i put on. thanks

This depens on what kind of derailer you have to begin with . As long as it has the range you will be okay if you adjust it the right way. I put a mega low range sprocket on my 7 gear cassete( changed from 28 tooth to 32 tooth) and did not have to change my derailer,however I had to adjust it properly. If your original cassete is an 8 gear to begin with, you dont need to buy a new derailer. I also have an 8 gear cassete with mega low on it. I do not see any significant diference between my 7 gear and 8 gear mega range derailers . All you have to do is make the nessesary adjustments.:-/

[42blue15]

The "MegaRange" gearing is not really any greater than normal, it was a low of 11T or 12T and a highest of 34T gearing, which was common then and now.

Originally Posted by toker_ace

Does a mega gear freewheel require a special derailler? I'm having problems with my derailler on a mega gear freewheel i put on. thanks

The "Mega Range" is an older/cheaper Shimano cassette setup that had a particularly wide jump between the largest and second-largest cogs. It looks visibly different than most other bicycle clusters and freewheels.

This Sheldon page shows them disassembling one:
The Shimano Mega 7 Freewheel

If this is what you have, then it appears that there may have been a particular derailler for it.
This Amazon page:
Amazon.com: Shimano RD-TX51 Tourney Mega Range Rear Derailleur 6/7 Speed Hanger Mount Black: Sports & Outdoors
has a (Shimano) Tourney derailler branded as "MegaRange",,,,, -and I know for a fact that all Tourney deraillers are not branded as "MegaRange".
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