Bicycle Mechanics - 2010 Sirrus Sport Drop Bar Conversion

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bennettm
09-27-11, 09:43 PM
I see there are several threads with similar questions, but I still hope to find some further clarification...
I am converting my 2010 Sirrus Sport to drop bars. I have the following parts:
Race Face Revolution 31.8mm drop bar
Shim 2300 triple STI levers
2 x Travel Agents
As it is, the crank is a 48 x 38 x 28 and the front derailleur is Altus. From reading around it sounds like I will need a road triple front derailleur - I was thinking of this one (http://www.amazon.com/Shimano-8-speed-Triple-Bicycle-Derailleur/dp/B003NV9AI6)
Link to 2010 Sirrus Sport stock tech specs (http://www.specialized.com/us/en/bc/SBCBkModel.jsp?spid=45858&menuItemId=0)
Any guesses as to whether or not this front derailleur will work, and if there is anything else I'm missing (besides bar tape, cable housings)?
Thanks!
Chris_W
09-28-11, 12:14 AM
It sounds like you have what you need to make it work, and that 2303 front derailleur should work with that crank and new shifters.
However, have you thought about fit? Hybrid bikes like your Sirrus tend to have longer top tubes than road bikes. If you use the current stem, you may find that the bar tops are the only comfortable place to ride - the hoods and the drops will require too much reach. You may therefore consider using a shorter stem by 1 or 2 cm.
Personally, I wouldn't bother making this switch with such a basic bike. You're sinking quite a bit of cash and time into it and ending up with something that is not really ideal. A new road bike equipped with 2300 components would not cost much more.
Sirrus Rider
09-28-11, 12:48 AM
I see there are several threads with similar questions, but I still hope to find some further clarification...
I am converting my 2010 Sirrus Sport to drop bars. I have the following parts:
Race Face Revolution 31.8mm drop bar
Shim 2300 triple STI levers
2 x Travel Agents
As it is, the crank is a 48 x 38 x 28 and the front derailleur is Altus. From reading around it sounds like I will need a road triple front derailleur - I was thinking of this one (http://www.amazon.com/Shimano-8-speed-Triple-Bicycle-Derailleur/dp/B003NV9AI6)
Link to 2010 Sirrus Sport stock tech specs (http://www.specialized.com/us/en/bc/SBCBkModel.jsp?spid=45858&menuItemId=0)
Any guesses as to whether or not this front derailleur will work, and if there is anything else I'm missing (besides bar tape, cable housings)?
Thanks!
Actually If you're going to retain your current crank you're going to need an IRC Alpina front derailer. A Shimano Road front derailer will not play nice with intermediate rings and brifters. (been there got the T-shirt) and brifters will not play well with front derailers intended for mountain bikes either. The rest of what you have should work fine.
Sirrus Rider
09-28-11, 01:01 AM
It sounds like you have what you need to make it work, and that 2303 front derailleur should work with that crank and new shifters.
However, have you thought about fit? Hybrid bikes like your Sirrus tend to have longer top tubes than road bikes. If you use the current stem, you may find that the bar tops are the only comfortable place to ride - the hoods and the drops will require too much reach. You may therefore consider using a shorter stem by 1 or 2 cm.
Personally, I wouldn't bother making this switch with such a basic bike. You're sinking quite a bit of cash and time into it and ending up with something that is not really ideal. A new road bike equipped with 2300 components would not cost much more.
What you say may be true; however, if you want a modern drop bar road bike that can handle fenders and racks from specialized that says 'Sirrus' on it it's the only way to get one.
also, One reason to do it is for the same reason people climb Everest, fixed junked cars, airplanes, etc. it's not because it's cost-effective or cheap, but because there's a certain wow factor.
I am currently evaluating the ergonomics of my Sirrus DBC. So far it is okay as long as the weight on the bike is evenly balanced. I did notice some hand pressure when I was hauling a trailer with it. I've only had two rides on it so far so I can't say for sure whether or not it needs a shorter stem. the only one definite negative I have observed is the bar end is right at the level of the top tube leading to some risk of the top tube getting dented in an accident and preventing the front wheel from being turned a full 90° to the top tube.
jimc101
09-28-11, 02:10 AM
What you say may be true; however, if you want a modern drop bar road bike that can handle fenders and racks from specialized that says 'Sirrus' on it it's the only way to get one.
Then you sound like you aren't in the market for a road bike, but a light touring or audax type bike; the Tricross from Specialized seems to fit your requirements better than the Sirrus.
Modern road bikes are all about being light weight, this does not mix well with racks, fenders are not an issue tho, as many mid range bikes will come with frender mounts.
For the costs, putting Sora your bike will come out similar to the cost of a whole bike, STI's are the single most expensive part of a dropbar bike, and for the low end of the market, buying these seperatly, can be almost the same as a complete bike.
Chris_W
09-28-11, 04:00 AM
Actually If you're going to retain your current crank you're going to need an IRC Alpina front derailer. A Shimano Road front derailer will not play nice with intermediate rings and brifters. (been there got the T-shirt) and brifters will not play well with front derailers intended for mountain bikes either. The rest of what you have should work fine.
I've successfully used a Shimano 105 FD (5603) with a 49-38-26 chainring combination without any trouble (with 10-speed chain). I would try the 2303 FD and see how well it works - I expect it will be OK.
I agree with the above post that the Specialized Tricross would be the most appropriate for this kind of purpose - I have one myself and love it.
fietsbob
09-28-11, 08:31 AM
The Front derailleur compatibility issue goes away with a Bar end shifter , at least on the left
as shimano's STI front. indexing just has big throws 1 for each chainring.
the left lever in the end of the bar has a continuous range of motion thru all 3 chainrings.
the Right side , is indexed, or not. a user choice..
Good luck..
bennettm
09-28-11, 10:53 AM
Thanks everyone for the input.
As far as the reasoning behind this project - I use my Sirrus for commuting and would like to do some touring with it, so the rack and fender mounts are a definite plus, but I also love drop bars over the flats (I was completely new to road cycling when I got this bike - first a mountain biker). Overall I would say I'm doing this for curiosity's sake and for enjoyment, so thanks for the advice and the warnings.
Needless to say I kind of really got into the world of road cycling and picked up a Tarmac Comp for when I'm not commuting, and I have to say that I've never had so much fun on two wheels before :)
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