Sizing & Geomtery for a Large Rider - Limited to Decathlon

Zelfer

Hi all.

I've won £650 worth of Decathlon vouchers which I've got to spend in about a months time, and am looking to spend it on a bike. I've been rather lethargic for a couple of years, but with summer coming, hoping to change that, spurned on by a colleague of mine who started commuting by bike in December who keeps laughing at me at the moment as he passes me stuck in traffic.

Options are spend it all on 1 bike outright, or 1 bike & keep the rest for 2 years worth of parts & a tool kit. Looking at the drop bar versions of the £600 540 Triban (2x10)and the £300 500SE (3x8) , and torn because of the sizing & geometry vs the components. Intended use is building fitness and a 12 mile road commute each way in mostly suburbia.

The 540 has 105 shifters, tiagra cassette, a prowheel (?) cranks and Mavic Aksium wheels, whereas the 500se is microshift stuff, 3x8 , and unnamed wheels.

I'm a 6ft6 bean pole with 34" legs & long arms, - so I'm on the upper limit of the 540's recommended sizing for height but their lower limit for legs, whereas the 500se, coming in a 63cm XL, probably has a better frame fit, and comes with a longer stem.

So - How do I determine which one to go with? Is the 105 that much better than the microshift stuff? How do I determine what the "correct" fit is and wether it's worth the component updgrade?

Ta!

markhewitt1978

Zelfer wrote:

So - How do I determine which one to go with?

Always get the best bike you can afford at the time

Is the 105 that much better than the microshift stuff?

Yes; although that's old 10 speed 105. Not the latest 11 speed 105, it's important to know they are very different.

ryanshattered

The 10s 105 is not well loved - regarded as a bit of a dud, whereas the 11s is excellent.
Is there any way you could top up the vouchers with an extra £100 to get the Ultra 700 AF? That's what I would personally do.
The XL (60) for that frame is recommended for people up to 6'6'' and inside leg of 34-37.5"

markhewitt1978

ryanshattered wrote:

The 10s 105 is not well loved - regarded as a bit of a dud, whereas the 11s is excellent.

Agreed. My first road bike had 5700, actually was recommended by a friend and I was pretty disappointed by it, if that's what road bikes are like you can keep it! Turns out the groupset was just pretty crappy. Changed it, at much expense, to 6700 and haven't looked back.

kajjal

If it fits go for the more expensive bike as it will ride better. One thing to try as you are at the top of the height range is flipping the stem into the upright position, they can do this for you in the shop in a minute or so. This brings the bars up higher.

If it is too small with the stem flipped upright you need to look at a different bike, like the 500se which comes in larger sizing.

mrb123

Kajjal wrote:

If it fits go for the more expensive bike as it will ride better. One thing to try as you are at the top of the height range is flipping the stem into the upright position, they can do this for you in the shop in a minute or so. This brings the bars up higher.

If it is too small with the stem flipped upright you need to look at a different bike, like the 500se which comes in larger sizing.

Wouldn't flipping the stem up have the effect of decreasing the reach though?

drlodge

Always go for the right sized/geometry bike. Always. A bike that doesn't fit you properly is useless and you won't ride it. You should try some bikes before hand (and preferably in the shop) to ensure you get the right size. Generally, a smaller bike is better than a larger one since you can't make a big bike smaller, however there is a trade off:
- a small bike can be made bigger by extending the seat post and stem, but there will be a larger drop from saddle to bars which may be too much
- a larger frame will have a smaller drop from saddle to bars making it a more relaxed feel, but it will have a longer top tube so you may feel a bit stretched.

kajjal

MrB123 wrote:

Kajjal wrote:

If it fits go for the more expensive bike as it will ride better. One thing to try as you are at the top of the height range is flipping the stem into the upright position, they can do this for you in the shop in a minute or so. This brings the bars up higher.

If it is too small with the stem flipped upright you need to look at a different bike, like the 500se which comes in larger sizing.

Wouldn't flipping the stem up have the effect of decreasing the reach though?

Yes it does but road bikes can have too much reach and drop for many riders. Depends on personal preference and your bodies proportions.

Zelfer

Thanks for the responses. I've had a chat with a DC bike specialist and they have recommended the 540, and confirmed that there is enough length in the seatpost to move it about. They have also offered a stem swap to a longer one if required; anyone would think they want the extra dosh!

Cheers for the 105 info, I hadn't realised that the ten speed was so poorly regarded, but I guess it's better than the 520s Sora stuff? I'm really not bothered by the triple over the ten speed.

The ultra af does look good, but no pannier mounts and lack of larger wheel clearance worries me slightly, the 540 can fit 28 and full mudguards, the 500se and ultra appear only 23 and full mudguards.

Off to see options tomorrow, I understand that DC don't let you test ride though to do a proper comparison :-(

daniel_b

Nice win there!

Decathlon bikes are very well regarded, and have lifetime warranty's on the frame.

I know someone who has a Triban 300, and loves it - additionally she bought a 51, rode it, took it in for a service, and they told her it was too small for her, took it back, and found her a new 54 - good service.

Nice mention for the Ultra above, that is a superbly reviewed bike, but sadly as you say, has no rack or mudguard mounts, which is a real shame, stunning looking bike though.

I think you are bang on the money for your £600 budget though.

They will let you ride it around the store though, and i would be surprised if you can't ride it outside a bit - which store do you go to?

I would get a trackpump whilst you are there, and potentially and have a good look around for some other bits - helmet perhaps if that's your bag, and or shoes, although personally, I would pick those up online.

I thought I read that some decathlon road bikes come with their own SPD-SL style pedal, which could be handy, assuming they are 3 point fixing, you would just need to find a suitable shoe to go with them.

Oh and here is a pretty glowing review if you ave not already read it:
http://www.bikeradar.com/road/gear/category/bikes/road/product/review-btwin-triban-540-16-49953/

Oh and just for another perspective, I have fitted full 5700 groupsets to my gf's Scott an my bro's Cannondale Caad 3, and both have performed faultlessly, no shifting, or other issues.

Zelfer

Ooh, good info on the size change, thanks. The problem I have is if i get the top size, and I needed a bigger one, where do I go from there? At least I'll ask the question.

Anks for the feedback on the older 105 stuff, good to have someone with experience not slag ittoo much!

I'm thinking the excess needs to go on some more suitable tyres &a mudguard to start with, but a Helmet is a good shout, my old one is very old so worth a replace. Track pump exists somewhere, will check.

SPD and spd-sl hmm, might ride flats for a while, think I have some cycling shoes from years ago (aka pre kids) somewhere!

Oh, and store is the Oxford one

daniel_b

Two options if the biggest is not big enough, a longer stem which they have already offered, and or a more setback seatpost, plus you have a modicum of slide room on the saddle rails.

Is your inseam 34, or do you take long trousers?
Reason I ask, is that I am 5ft 10 and have a 34 inseam, so long legs, short body.
Sounds like you might have the opposite problem, and need a technically racier bike with a longer top tube than the norm, though of course stem/seatpost choices can go some way to address this.

Not been to the Oxford store, know the Reading one well, and Surrey quays is good too.

One last option if it is genuinely too small for you.
Buy bikes for all or some of your family, and then use the equivalent money to buy a bike that will fit you.
Plenty of good deals out there on last years bikes I expect.

drlodge

A seat post with longer set back is a bit of a red herring, since just by moving the seat post up it moves backwards, to the same position it would be on a larger frame. A larger frame may have a slightly more relaxed seat tube angle though which will put the saddle further back.

The thing to watch for on a smallish frame is how much the stem can be raised by. There's probably a limit of 25mm or so of spacers possible and coupled with a short head tube may make the saddle-to-bar drop too much.

Zelfer

@Daniel B -
I'm 34" as measured using the "book against the wall method" - and I normally get a 33" trouser. I guess the only way to really find out is to try them.

I had considered selling the vouchers to someone and spending the money elsewhere, but most people seem to point back to decathlon for "cheaper" bikes nowadays, so felt like a loss.

@drlodge - thanks for that heads up, i'll check out the spacer query. One of my concerns is the "foot into the wheel while turning" issue, given that I've got size 13 feet I really don't want the effective top tube length to be too short, otherwise this might be a problem.

Will let you know in a couple of hours

daniel_b

I hope the visit goes well.

As your inside leg is the same as mine, your torso must be 20cm longer, so I suspect the drop from saddle will be an unlikely issue, as that is a fit issue I need to get around with a short torso.

I think the key for you will be an adequate top tube length.

Intrigued to hear how you get on.

Zelfer

Daniel B wrote:

I hope the visit goes well.

As your inside leg is the same as mine, your torso must be 20cm longer, so I suspect the drop from saddle will be an unlikely issue, as that is a fit issue I need to get around with a short torso.

I think the key for you will be an adequate top tube length.

Intrigued to hear how you get on.

Thanks.
Took both 500se in xxl and the 540 in xl for a mini ride around the store, the 500se did feel to have slightly more space between foot and wheel. Ride position on both seemed OK, a bit unnatural but I'm sure that will settle in. Didn't mess about with the stem at all on the 540, it seemed about the same as the 500se. Really liked the bars on the 540, slightly narrower between the bars, but the bars in the resting position are shaped quite wide, whereas the 500ses are round, and not as comfortable.

So, went with the 540 in the end as the parts were better and I like the idea of proper mudguards, looking for the SKS bluemels in 35mm, unfortunately they didn't have them in stock, only the raceblades .

Thanks for your help!

daniel_b

Sounds like a successful mission - be good to see a pic of it set up for you, saddle height etc etc if you are able.

SKS Bluemels are available online for not very much, £18 odd on Wiggle.

Someone on here recommended tortec mudguards, and the ones I bought come with a twin reflective stripe down the sides - they do seem better than the SKS ones, all of mine crack eventually at the rear mounting bridge, but only time will tell if these are better - just fitted them to my gf's new winter bike, just in time for summer ;-)

The only thing that didn't impress me was the rear mounting bracket which was of the stiff plastic variety - had one of these on a set of sks guards, and unsurprisingly it snapped - luckily I had a spare SKS metal one in the parts bin, so used that instead.

One thing I will say for tortec versus sks, is that the natural curve of the guard is far shallower than the sks, in that I had to force it down at the back to get it to follow the curve of the wheel - which does mean it has a very nice tight and taut fit, but not sure if that will compromise longevity at all - again time will tell.

The other thing you might want to bear in mind, is BC membership for legal advice, and also it gives you 10% off at Halfords, and 10% off at CRC on transactions of £99 or more.
There are also usually deals around on membership for first timers if you google.

Enjoy your first ride, Sunday looks prime for it!
Assuming you have it already of course?

Zelfer

Thanks. Yep, have the bike here now and my colleague dropped off some flat/SPD pedals he had spare, so just fitted those and have had a wobbly ride in the short sunny spell we are having.
Feels fast as heck, a little scared at how it picks up speed, having been used to hybrids.

Thanks for the tortec recommendation, I'll have a lock. I'm very nervous about traffic, so the more reflective the better, have just picked up some 3m spoke reflectors things to fit as I can't stand those yellow reflectors.
I have been considering BC and CTC (or we are cyclinguk as it now is) membership for the 3rd party liability and accident legal cover.

Will get a picture of it after the kids are in bed, weather depending, before I contaminate it with panniers!

wolfsbane2k

How are you getting on?

You've probably done the right thing with the 540.
I've just returned my 500se and replaced it with the 540 - it's a quite a different bike to the 500se.
Will be interested in seeing the setup you've got yours on, I'm 6ft 7 with 33" legs, and probably have to get a longer stem to replace the stock one, as this mornings first ride felt very cramped. there is "some" flex in the seat position that will probably help as well.