# Aluminum 5 vs. Carbon 3 Synapse



## Biffster (Mar 13, 2011)

Hello everyone,

Well the weather was finally decent enough in Ohio to go to my lbs and test ride a couple of bikes I've been looking at. Specifically, I was wondering how good the Aluminum synapse frames were. The ride was spectacularly smooth and just as an afterthought, I took the carbon 3 out (I would have loved to take out a carbon 5 so the components would mostly match up , but they didn't have one). The ride quality was no better, but I felt like I was going a little faster. A guy working there pointed out the bottom bracket size between the two and thought maybe that was tranferring more of my power on the carbon 3. The bottom bracket on the Carbon 3 frame is absolutely massive, however the aluminum frame is using oversized tubing and both are setup to use the BB30 so I'm not so convinced. FYI, I'm built like a climber, so I have a hard time believing I'd be able to flex the frame much. 

I wonder how much of it was the wheels, tires, and components(Ultegra vs 105, Shimano RS80 carbon vs RS10 aluminum wheels, and 700*23 vs 700*25 tires)? 

Also, could the chainstays be less rigid on the aluminum bike? Maybe the frame was flexing their and that was sapping some of the power?

Any thoughts are welcome. I've been riding for a long time and the last time I purchased a bike was 16 years ago. A lot has changed since then!


----------



## 8toes (Feb 28, 2010)

I jusy purchased a 2011 Synapse 5 Alloy 105 last Saturday, and being in Canada, I have not had a chance to ride it yet. I will be commuting to and from work all week since the weather is supposed to finally let up. I did love the test ride as well. I am a bit larger than you (6'1" 210lbs) so I should think you would be quite happy with it.

Cheers,

Brian J


----------



## ph0enix (Aug 12, 2009)

Biffster said:


> could the chainstays be less rigid on the aluminum bike? Maybe the frame was flexing their and that was sapping some of the power?


It's the wheels. The RS10s are noodles.


----------



## ziscwg (Apr 19, 2010)

Biffster said:


> Hello everyone,
> 
> I wonder how much of it was the wheels, tires, and components(Ultegra vs 105, Shimano RS80 carbon vs RS10 aluminum wheels, and 700*23 vs 700*25 tires)?
> 
> Also, could the chainstays be less rigid on the aluminum bike? Maybe the frame was flexing their and that was sapping some of the power?


Keep in mind what you are riding. It is a "comfort" or long haul bike. So, they design a little flex here and there into the frame. 

The wheels do matter. Flex happens a lot in less expensive wheels. It's hard to explain, but you get this "give" in the more flexy wheels. You dont always notice until are on a better set.

700 23 vs 25 is just ride comfort. I run 25 because I'm used to 140 mm of squish on my bikes. You can run the 25 at lower pressure to smooth things out.

If you want something more rigid, look at the CAAD10. I think they are cheaper too than the carbon synapse. Riders have been raving about how well they ride for Al. There have even been comparisons to many carbon frames where the CAAD10 was smoother. That is totally subjective, but can be valid. I have not had one on a long ride, so I cannot give first hand experience


----------



## ARPRINCE (Feb 12, 2011)

ziscwg said:


> ....The wheels do matter. Flex happens a lot in less expensive wheels. It's hard to explain, but you get this "give" in the more flexy wheels. You dont always notice until are on a better set.


 I also got the Syn Alloy 5. What wheels would be a good replacement within 200-250 range?

Thanks


----------



## Brazos (Jun 20, 2009)

I have a Syn Alloy 5 and new wheels made a huge difference (stock were RS-10's). I bought Ultegra 6700 (Tubeless) wheels for a little over $300 (look at Chainreaction, Ribble, etc for those prices) and the bike is much better. It was faster, more nimble, much more stable downhill, and climbed much better. Just made a great bike better.


----------



## clydeosaur (Jan 5, 2010)

I had RS10's on my Six 5 until I got hit. They flexed ALOT. As soon as I got rid of them, I realized how stiff the bike was & how weak those wheels were.


----------



## Biffster (Mar 13, 2011)

Thank you everyone for your replies! It looks like most think the difference is in the wheels. I've always heard that's your biggest bang for your buck when upgrading so I guess it makes sense. 

Although I like to ride hard, I'm not doing any racing, so I'm pretty much sold on the synapse. Got a family and can only get away for 1 to 2 hrs. once or twice a week anyways. I did take one of Cannondales more race oriented bikes out and it didn't feel any faster than the synapse carbon w/ the rs80 wheels. The ride was definitely worse though. Road chatter that was pretty much gone on the synapse was back in several places on the race bike and the jarring impacts over potholes were back as well. 

One other nice benefits of the aluminum over the carbon synapse I didn't mention b4 was the noise. The aluminum was dead quiet while the carbon "hummed" along. 

I think you got the perfect commuter bike, Brian. Obviously, I'm leaning towards the aluminum too. Definitely going to checkout Brazos sites, thanks.


----------



## Biffster (Mar 13, 2011)

Went back into the lbs and test road the synapse alloy 5 and also a new CAAD 10 the other day. Both had Shimano rs10 wheels on them and did help answer my earlier question. The CAAD 10 felt slightly more snappier, but not much. So, I'd definitely chalk it up to the wheels being the big difference between the synapse carbon 3 vs. synapse alloy 5. 

p.s. The ride on the CAAD 10 is less smooth, but not by much. It looks like they took the chainstay section of the frame off of the synapse. However, pinching the middle of the top tube does make it flex, which makes me nervous. The lbs still has a CAAD9 in my size, beginning to wonder if I should be looking at that?


----------



## ziscwg (Apr 19, 2010)

Biffster said:


> However, pinching the middle of the top tube does make it flex, which makes me nervous. The lbs still has a CAAD9 in my size, beginning to wonder if I should be looking at that?


OK, that guy who started this BS about being able to pinch an Al top tube and notice the deflection is really getting on my nerves. Al work hardens and gets brittle with very little deflection. So, those frames would be gone in a matter of a few rides or sprints. 

Come on people. :idea:


----------



## gevad (Jul 28, 2011)

Sorry for resurrecting this old thread, but I don't have enough posts to start my own.

Just wanted to report that I just got a Synapse Alloy 5 and really like it. I tested it back to back against a Synapse Carbon 4, and while the Carbon 4 was somewhat smoother, to me it didn't handle any better and it wasn't $1000 better.


----------

