Nervar 6 Speed Mega Range Screw On Freewheel Cassette 14/34 Hi-Range for Shimano & Other Brands, Easy Uphill Riding, Black/Silver Finish

I'd already upgraded the chainset on my bike to give it a higher top speed and thought this would be worth a go as it was time to replace the original cassette. It screwed onto the wheel as normal but I then found that my chain wasn't long enough. I'm handy with bikes so I just added an extra two links. If you can't do this yourself and your setup is like mine, you'll need a 116 link chain. I then tested it out and the gear changes were smooth and easy, great until I tried to backpedal on the biggest cog. No matter how hard I try, I can't adjust the rear derailleur so that the chain will stay on the largest cog when I backpedal. This isn't really a problem: I've just adapted my riding style to make sure I'm in second gear or higher when I come to a stop. Given the huge difference this makes when climbing very steep hills, it's been a very worthwhile purchase and certainly a lot easier and cheaper than upgrading to a 7 or 8 speed cassette and having to buy and install a new gear shifter. Very happy overall.

This does its job, however, it is not as precisely machined as an original Shimano. The freewheel removal tool struggles to get in and out smoothly as on the original Shimao freewheel. Moreover, the edges of the metal ramps in the cogs are not as sharp as in the original. Next time I would spend a few pounds more for the original Shimano.

on the other end of a 30 52 chainring you get a range of 24 to 100 inches fwd for each pedal rev or speed jump from 7 to 40 mph. the wheels can be commanded to roll from 3/4 of a revolution to 4 revs for one pedal stroke. this means that without getting out of the saddle the 34 cog painlessly enables you to climb hills that are long and steep enough to stop some cars and the smallest will allow you to overtake a lorry on a slight descent.whats not to like.why struggle out of the saddle,hating cycling,walking up hills with an 11 28 that came thoughtlessly preinstalled on the bike when you can own this instead.

The company were very good. The item arrived quickly and we're very helpful in returning it when it didn't fit hubby's bike.

Brilliant