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Old 08-27-10, 06:33 AM   #1
bobinski
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lightening a Downtune 9fs

Hi,
Bought my 12 yr old son a 9fs last year. He is using it more and more but understandably complaining it could be lighter!
I have new lightweight skewers from Planet x for the wheels and will replace the saddle with a charge plug. The bike does not get folded too often so an allen bolt to replace the seatpost qr.
Seat post? seems a fair bit could be saved for not much of my UK pounds.
Possibly the handlebars too. and break levers?
anyone gone on the weight saving route with this bike? did a search but it returns a lot of hits

Some corrosion/rust on the main qr where the body separates. I would love to source a light weight replacement but have not found anything similar yet. any help would be greatly appreciated.
cheers
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Old 08-27-10, 06:51 AM   #2
jur
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The fist place to do weight saving are the wheels. A new wheelset would be needed, not cheap but still the most bang for buck. And even before the wheels, the tyres. Get some light weight tires.




Just be warned: The weight weenies path is one of no return... on investment.
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Old 08-27-10, 07:30 AM   #3
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It may be cheaper to sell the FS and buy a Nova than to put money into a weight loss program for the FS.
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Old 08-27-10, 11:41 AM   #4
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When I got my Dahon Vitesse a few years back I was unhappy with the weight and set about trying to figure out the most efficient and cost effective way to lighten it. I was able to shed about 1 kg without buying any particularly expensive components, though the total cost of all the upgrades would have come to a fair amount. . . But you'd really have to (as I did) weigh the various components of your bike and find out which are most worth swapping out. For instance, on my Dahon the alloy handlebar was, for some peculiar reason, about 220 grams. . . there's no reason for it to be that heavy, there are plenty of cheap, decent alloy bars that are around 130g. The pedals were clunky and I replaced them with some very light, non-folding tioga pedals which saved about 300g. The chainset was a piece of crap so I spent some time trying to find a good alternative (with correct chainline) and opted for a second-hand Shimano 105 chainset on ebay, that saved another 300 grams or so.

The end result was worth the effort but my Vitesse is likely significantly lighter than the Downtube FS in the first place, i.e. 1kg as a percentage of the overall weight is more significant whereas with the Downtube it may not really be that noticeable as the fork and frame are heavy. A suspension fork of that type is about 1kg heavier than standard forks.

The tires may or may not be on the heavy side, there's probably scope to lose weight there but you have to consider comfort and durability.
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Old 08-27-10, 04:17 PM   #5
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I don't know what grips the DT has but you might want to try these:

http://www.chainreactioncycles.com/M...?ModelID=39256

I might give them a go, a lot of people seem to like them.
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Old 08-31-10, 02:34 AM   #6
bobinski
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Jur,

I know.Rotating mass and all that. But the cost is too great for a new wheel set. Not looking for a weight weenie approach-that is reserved for my road bike or a Bike Friday if i can ever afford one-but looking at the seatpost, handlebar etc there must be significant weight savings. the dead weight. perhaps even the suspension fork which seems to serve little purpose.

Chagzuki,

grips are already sorted and have the benefit of more comfortable hand extensions. Interested in your other changes though and will pop over to Downtube to get measurements for things and then have a look at Ebay.

Thing is, my son loves his bike and if i can lighten it at reasonable cost and keep him interested in cycling as he approaches his teenage years then even better.

anyone have any thoughts on replacing the quick release hinge other than through Downtube?

cheers
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Old 08-31-10, 02:56 AM   #7
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That's the trouble - there isn't significant weight savings in skewers. These are usually tackled when just about everything else has been done. No point in saving 50g...

For the hinge QR, it is likely to be the same as common seatpost QRs - just disassemble it and compare to the seatpost QR.
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Old 08-31-10, 07:22 AM   #8
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I don't know if you've replaced the stock DT tires, but if you put on some 100psi marathons or similar you'll notice some significant zippiness. If you live in a flat area, that's probably all you need to do. Unless of course you have to carry your bike up a 3 story walk-up.
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