So....is it too small?

norvernrob

My winter bike I mean!

The story is basically this: I'm 5'9, 32" inside leg and ride a 54cm Foil which I love and feels great. A couple of months ago I picked up an end of season bargain 53cm Cube Peloton race, I knew the frames come up small but thought it would be fine.

To match the foil setup as much as possible I fitted a 25mm setback seatpost and 120mm stem. It feels ok as far as reach and saddle height goes, except I am experiencing severe leg fatigue which riding it. When I'm on the Foil there is nothing between my mate and I, on the cube he destroys me. At the weekend I suffered lower back and upper thigh pain, both things I never get on the foil. On one long climb I couldn't pedal fast enough to even breathe heavily my legs were so dead.

When I got home I dropped a plumbline from the tip of each saddle (saddles are the same length) . On the foil it was 4cm back from the centre of the BB, on the cube it was 0.5cm back.

The trouble is the saddle is already back to the stop marker, so I don't see how I can do anything about it, never mind moving it back a whole 3.5cm.

I've got a fit booked at cadence in January on both bikes, but I don't want to waste my time there if the cube is too small!

Has anyone got any suggestions, and is it likely that a 3.5cm difference in saddle fore/aft can really make that much of a difference? I hope so because I'm useless on it!

Thanks for any replies.

Rob

imposter2.0

I don't understand why you are wasting time stressing over a bike which (for any number of reasons) clearly doesn't suit you, when you have a Foil sitting at home, which clearly does?

sigorman85

Crank arm length maybe?

norvernrob

Imposter wrote:

I don't understand why you are wasting time stressing over a bike which (for any number of reasons) clearly doesn't suit you, when you have a Foil sitting at home, which clearly does?

Because when it's wet, and the roads are covered in salt and filth I want to ride a cheaper bike and not wear out components or risk coming off a 6 grand bike. It's insured of course but I'd rather not break it! We climbed Riber Road at the weekend and I nearly came off twice due to the wheels slipping on dead leaves.

norvernrob

sigorman85 wrote:

Crank arm length maybe?

172.5 on the foil and 170 on the cube, so my knee is actually 3.75cm further forward on the cube.

imposter2.0

NorvernRob wrote:

Imposter wrote:

I don't understand why you are wasting time stressing over a bike which (for any number of reasons) clearly doesn't suit you, when you have a Foil sitting at home, which clearly does?

Because when it's wet, and the roads are covered in salt and filth I want to ride a cheaper bike and not wear out components or risk coming off a 6 grand bike. It's insured of course but I'd rather not break it! We climbed Riber Road at the weekend and I nearly came off twice due to the wheels slipping on dead leaves.

ok - but if you're serious about winter riding, then select a winter bike on something other than 'being a bargain'...

Bozman

You go up a frame size for Cube and Scott's are slightly bigger than advertised, I'd guess that you've got about 30 odd mms between the two TTs, I doubt that you'll pull that back.

norvernrob

Bozman wrote:

You go up a frame size for Cube and Scott's are slightly bigger than advertised, I'd guess that you've got about 30 odd mms between the two TTs, I doubt that you'll pull that back.

That's what I was fearing tbh. I've got the bike fast fit app on my ipad so will have a quick look tomorrow. I know KOPS isn't an absolute but I've got a feeling mine is a long way forward, as from memory it was about 1cm forward on the foil.

Bozman

NorvernRob wrote:

Bozman wrote:

You go up a frame size for Cube and Scott's are slightly bigger than advertised, I'd guess that you've got about 30 odd mms between the two TTs, I doubt that you'll pull that back.

That's what I was fearing tbh. I've got the bike fast fit app on my ipad so will have a quick look tomorrow. I know KOPS isn't an absolute but I've got a feeling mine is a long way forward, as from memory it was about 1cm forward on the foil.

You might be alright and I doubt that there's 30mm difference, I had a similar issue with a Cube Attempt that I'd bought for a winter bike and I just couldn't get the right fit, I sold it on and bought a CR1 in the end.

letap73

Your setback position on the Cube is obviously completely wrong and is what is causing the problem. Although the Cube frame is smaller, your bottom bracket to saddle height on both bikes should be exactly the same and assuming seat tube angle is similar then you should be able to achieve the same saddle set back. If the front of the saddle is only 0.5 cm behind the bottom bracket with a 25 mm set back post and the saddle pushed all the way back I would be surprised. This would only make sense to me if you actually put the seat post the wrong way around.

Any chance you can put some pictures up?

I ride a bike which has a top tube which is only 5mm longer than your cube - yet can achieve a set back of 8 cm easily with a 25mm set back post.

964cup

The Cube has a 53.5cm effective top tube. The Scott's is 55.

In addition, the Cube's seat tube is at 74 degrees; the Scott's is at 73.3. Assuming you run a 71cm centre BB to saddle top height, that puts the Scott's saddle 8.4mm further back than the Cube's.

Both combined mean the Cube has a much shorter reach than the Scott, and if the Scott is comfortable for you, you won't get the Cube to fit.

That said, I agree with the letap73 that you can't have the post set correctly; assuming the saddle is, say, 5cm from rail centre to top, the seatpost clamp including the layback should be 20.7cm behind the centre of the BB on the Cube. Centre saddle rail to nose of saddle is about 15-16cm, so you should be at least 4cm behind the BB or thereabouts, unless your seat height is much too low.

letap73

964Cup wrote:

The Cube has a 53.5cm effective top tube. The Scott's is 55.

In addition, the Cube's seat tube is at 74 degrees; the Scott's is at 73.3. Assuming you run a 71cm centre BB to saddle top height, that puts the Scott's saddle 8.4mm further back than the Cube's.

Both combined mean the Cube has a much shorter reach than the Scott, and if the Scott is comfortable for you, you won't get the Cube to fit.

That said, I agree with the letap73 that you can't have the post set correctly; assuming the saddle is, say, 5cm from rail centre to top, the seatpost clamp including the layback should be 20.7cm behind the centre of the BB on the Cube. Centre saddle rail to nose of saddle is about 15-16cm, so you should be at least 4cm behind the BB or thereabouts, unless your seat height is much too low.

Excellent mathematical analysis, however, in terms of reach, the Scott's longer top tube is countered by the Cube having a steeper seat angle - this means to achieve the same saddle position wrt bottom bracket requires moving the Cube saddle back.
See the two diagrams:
http://velonews.competitor.com/2011/02/ ... les_161205

tom3

I would say yes from reading the very first line. Always size up with cube.

Sell it before you do yourself an injury. You could consider a 54 speedster?

The performance difference would be normal. I drop my brother like a stone on his raleigh airlite but the canyon ultimate is a different story. Also, the raleigh frame is their 53cm (mid sold) but the canyon is their large.

norvernrob

964Cup wrote:

The Cube has a 53.5cm effective top tube. The Scott's is 55.

In addition, the Cube's seat tube is at 74 degrees; the Scott's is at 73.3. Assuming you run a 71cm centre BB to saddle top height, that puts the Scott's saddle 8.4mm further back than the Cube's.

Both combined mean the Cube has a much shorter reach than the Scott, and if the Scott is comfortable for you, you won't get the Cube to fit.

That said, I agree with the letap73 that you can't have the post set correctly; assuming the saddle is, say, 5cm from rail centre to top, the seatpost clamp including the layback should be 20.7cm behind the centre of the BB on the Cube. Centre saddle rail to nose of saddle is about 15-16cm, so you should be at least 4cm behind the BB or thereabouts, unless your seat height is much too low.

71cm is exactly the saddle height I have on both bikes, checked and double checked.

letap73 wrote:

Your setback position on the Cube is obviously completely wrong and is what is causing the problem. Although the Cube frame is smaller, your bottom bracket to saddle height on both bikes should be exactly the same and assuming seat tube angle is similar then you should be able to achieve the same saddle set back. If the front of the saddle is only 0.5 cm behind the bottom bracket with a 25 mm set back post and the saddle pushed all the way back I would be surprised. This would only make sense to me if you actually put the seat post the wrong way around.

Any chance you can put some pictures up?

I ride a bike which has a top tube which is only 5mm longer than your cube - yet can achieve a set back of 8 cm easily with a 25mm set back post.

Thanks for the detailed replies!

Time for a confession :oops: I've just checked again, seatpost is the right way around, saddle is indeed as far back on the rails as it will go. So going by your post something had to be wrong. And it was.

The bike was on the turbo with the back wheel off the ground and the front wasn't on the riser block, so the bike was angled forwards. :oops: I did the foil on the floor so the measurement for that was right, but the Cube is exactly the opposite of what I thought it was - the saddle is more like 6cm behind the BB (I'll measure exactly tomorrow) so I'm sat much further back than I am on the foil.

Good job I posted as I may well have missed that! Thanks again for the replies, I'll fit it up the same as the foil and give it another go. If it's still no good I'll just get a cheap foil

Rob

letap73

From what you have said above it seems possible to achieve a fit on the cube - although you are likely to have quite an aggressive fit. Like I said previously the steeper seat tube of the cube counters the effect of the longer top tube of the Scott. Once you have corrected the setback, take a measurement from the saddle tip to a point on your hoods - I usually take it to the point where the hood starts to curve up, the measurement should be the same for both the Scott and the Cube (measure to both hoods). You may achieve the same measurement by making adjustments, although I suspect you may have a greater drop from the saddle height to the bars on the Cube.

norvernrob

letap73 wrote:

From what you have said above it seems possible to achieve a fit on the cube - although you are likely to have quite an aggressive fit. Like I said previously the steeper seat tube of the cube counters the effect of the longer top tube of the Scott. Once you have corrected the setback, take a measurement from the saddle tip to a point on your hoods - I usually take it to the point where the hood starts to curve up, the measurement should be the same for both the Scott and the Cube (measure to both hoods). You may achieve the same measurement by making adjustments, although I suspect you may have a greater drop from the saddle height to the bars on the Cube.

Thanks, that's exactly what I've just been doing! I ended up moving the saddle 2cm forwards to get the same fore/aft as the foil, and the measurement to the hoods is 1cm shorter on the cube. I can rectify that with a 130mm stem as I've already got a 120mm one on there. Saddle-bar drop is ok. I have it slammed with no spacers on the foil so not much difference if I leave a couple on the cube.

Thanks again for the replies, I'll give it a bash this week and see what happens. At least I know it can be fitted the same as the foil so I'll not be wasting my time taking it to the fit.

letap73

Or you could take off 0.5cm - 1.0 cm of spacers of the cube rather than change the stem!