Questions about purchasing bicycles and parts
25 posts • Page 1 of 1
Well I finally got my new bike after a month of waiting - a Merida 905 with Ultegra components and upgraded wheels. I have only taken it for a few short rides but I have a couple of questions / concerns:
Regarding changing gears, I find that if I'm on the small cog at the front and the biggest at the back, the front derailure wont pull the chain over to the big cog unless you move across a couple of cogs on the rear. Is that normal? Is it ok to use the full range of 10 rear cogs and only the large front one or is it better to try to keep the chain straight? If I pedal backwards with a lot of bend on the chain it tends to fall off the front sprocket.
The other issue is regarding the handlebar positioning. The bike shop offered no assistance when I picked up the bike as far as fit. I had never test ridden the bike either as I had them order it in for me and they didn't have any on the floor for me to ride. Anyway, I have read a few articles on how to do the correct setup but I am just a bit concerned about how far forward I am reaching and how much weight is on my hands.
Is it normal to take a while to get used to a drop bar when coming from a mountain bike?
Am I correct in assuming there is no way to raise the handlebars?
What is the normal procedure if you buy a bike and you want a different length handlebar stem - do you have to pay the full price for a new one and keep the original or should the bike shop change it free of charge?
Any advice appreciated.
I have a tiny bit of trouble with this too. From what I can tell everything is fine distance wise and if I shift things around with more weight on the saddle, I feel like I'm sitting too upright.
If I adjust the seat closer so I have my arms any more then just slightly bent I feel like i'm going to throw myself over the bars when pedalling hard and just wind up gripping the hoods higher to over compensate anyway.
I've gotten sort of used to the position though, I think it might just be building hand strength as you rest on a different part of your hand on hoods vs a flat bar.
Last edited by Shard on Tue May 20, 2008 10:56 am, edited 1 time in total.
You should be able to change from the small to large chainring with the front deraillieur whilst the chain is in any position on the rear cassette. As this is a new bike it is likely that the front deraillieur needs some slight adjustment.
Yes it is much better to keep the drivetrain (ie chain and cogs) as straight as possible. However it's your bike and you can use it how you like
With regard to your riding position and stem length. You will find that your flexibility will increase, the more you ride and that you will become accustomed to riding in a lower position. The bike shop may change the stem for you at no cost or reduced cost. It depends on the shop.
If the stem is located at the top of the steerer then it is possible to raise the bars a little higher by flipping the stem. Assuming the bike is the right size for you, and the steerer wasn't cut too short, then the bars should be more than high enough. In extreme you could also flip the bars (not)
There's no definitive rule that says you can't use the the largest sprocket at the rear while on your large chainring but the general view would be that you wouldn't do it. Partly because it just distorts your drive line but more because it's a nothing gear which duplicates others which are available to you and are more flexible. If you are using your large chainring and need to drop down gears you can use 7-8 of your 10 sprockets but you are better off then dropping to your smaller chainring (in most circumstances). Similarly you would not use your smallest sprocket when on your small chainring. If your chain length is right and your drive train is telling you not to do it - don't do it.
For a perhaps clearer explantion you could start here: http://sheldonbrown.com/gears.html
It might have been wise to have established what the fitting ground rules were before you put cash down, but having said that any decent LBS should accommodate fitting you to your bike properly. The matter will be what they will do for free and what they will charge you for. If they don't help, engage a shamen to hex them or something and find an LBS that will.
Straydog, your first post could very well have been posted under my name. Same situation, exactly the same bike, same problems.
But in my case the guy from the lbs I bought it from was very helpful. Before I rode off for the first time he showed me how to work the gear changes and advised me to keep the chain as straight as possible as often as possible.
The riding position felt very strange to me. But that was what I expected. The thing you can't guess at is how different it feels and how long does it take to decide that either I can get used to it or this is wrong.
I decided pretty much straight away to move the seat forward and then after a week I ordered a shorter stem. Matt, from the lbs of purchase, didn't charge me for any fitting queries/tinkering or for the shorter stem. He just took my original stem and put it with his others for sale. Suited me as I wasn't going to use it and it was virtually brand new.
I felt that my position definitely improved with the changes and I'm actually spending more and more time in the drops with each ride. And that's going from a mind set of "I can't get used to riding in the drops" because they felt too far away.
I think (and this is just my personal opinion with nothing to back it up) that when you go from a flatbar or mtb, as you and I have, you have to be prepared to put up with some comfort problems. The riding position is VERY different and no-one really warns/advises you about that.
When I say "no-one" I mean guys from the lbs's you visit. And a spin around the car park or even around the block really won't warn you about the reach issues. Test rides I had, I rode the bikes in a mtb position only holding on to the top of the bars. I was too scared to go onto the drops or even the hoods because they were unfamiliar and I feared putting a new bike that I didn't own down.
I've done around 750kms on the bike now and can honestly say that the 40-60km rides are now comfortable, I actually feel good and confident on the bike. The 100km ride on sunday I felt discomfort through the neck and lower back beginning around the 70km mark. This I put down to it being the longest (by about an hour all up) I've ever ridden continuously.
So I think part of it is persistance.
I'd be interested to hear what other more experienced riders think, and their opinion on the space between the handle bars and the seat and handle bar height.
Hope it all works out straydog and you start enjoying the bike.
Use above as a guide only. I found it to be pretty accurate. The most important thing is seat height and setback then adjust reach accordingly. Reach depends alot on flexibility and how conditioned you are.
I can't believe they wanted to charge for fitting to their bike!
Edit: another fit calculator
Search Biomechanicalcyclingv6english in google and download first hit. Again I found it works for me, it was put together by a biomechanist (if there is such a word) and only need 2 measurements, pretty easy.
You'll need to get your seat position right first. It's the basis for everything else. There are no hard and fast rules (everyone is different), but a good starting point would be to have:
1. The saddle level (that is level from the point of the nose to the tip of the flare at the end.
2. The nose of your saddle roughly aligned with the rear of your bottom bracket, or maybe a smidgen behind it.
3. The saddle set for a height where your leg still has a slight bend in it when at the bottom of your pedal stroke when your foot is flat (when the crank is at 90 degrees to the ground). Make sure you have your riding shoes etc on when doing this.
Then for the handlebars a starting point for reach would be that when your hands are in the drops behind the brake levers your elbow should be at 90 degrees to where your hands are, not slightly straightened out or tucked back in by you. Another rough guide for reach is that when looking at your front hub from the saddle (with your hands on the bars) it should be obscured by, or be just behind, your handlebars. The handlebar height is up to you but a road racer will typically have it an inch or two below the saddle.
These are starting points ONLY and you will need to adjust to fine tune your comfort and to match your type of riding.
Google 'bicycle fitting' and you will get a fair range of websites that describe some variation on these ideas.
That's atrocious. Name and shame!
Of course, hindsight is always 20/20, but that should have rung the alarm bell to go spend your money somewhere else where they're a bit more customer-friendly.
I reckon with most road bikes you will have trouble getting the seat nose as far forward that it is level with the rear of the bottom bracket. I bought a seat post with zero set back to move forward on the bike and with the seat slid forward on the rails I am approaching 5cm back from the centre of the bottom bracket with the nose of the saddle, which I am told is the limit of forward location of the seat under uci rules. Sorry not having a go Jean, just my experience with my bike. It took me 12 months of slow evolution as my miles on the bike and flexibility on the bike improved, to arrive at the riding position I have now
Yeah that lbs is a good advert for buying over the net.
I agree with j.r. hawkins.
I guess we don't know all the particulars in your case.
I rode 4 similar bikes in 2 different sizes with 4 different configurations, on two separate days. Then later I had their 'fitter', who turned out to be the owner, fit me to the two different frame sizes and advise me which I should buy. Then I had them spec it up with the mix of components I wanted. I had to wait about 3 months for that frame size and configuration to become available. By then, next years model just happened to have much the same confuration and more, AND it was $200 cheaper!
I wasn't asked for a cent until I picked it up at the shop, and it came with a 'free' service after a month.
I reckon you could have got a better deal.
Don't know about the UCI rules, but it depends very much on the geometry of your frame in combination with that your seatpost/saddle will allow. The nose of my saddle actually overlaps my bottom bracket a touch. Cannondale 2.8s were a notoriously 'tight' geometry in their day.
The point was simply for straydog to get the nose of the saddle behind the BB (if it is not there already) as a starting point and play with it from there.
, Yeah I agree with the play with it from there bit too. I changed seat twice, handlebar stem, stem height numerous times, seat post and pedal cleat position on the shoe numerous times. Now I'm pretty aero when I need to be and comfortable finally.
Saddle height: get a helper to hold the bike. Sit on saddle, heel on the pedal with crank at bottom of the stroke. Leg should be almost straight. When pedalling (back pedalling) your hips should not rock at all
Saddle angle: level, or slightly (~5 deg) tilted up at nose. Use a long ruler to gauge it.
Saddle position: nose 5-7cm behind the crank axle
Saddle-handlebars: put your elbow at the saddle nose and hand alongside the stem. Fingers should stretch to about 4-5cms behind the bars.
Riding a road bike is quite a different feel to a MTB, especially if your MTB is set up for trails and downhill ie. bars high and close cf. saddle. You will get used to it in time, but you should still feel comfortable. Sore neck/shoulders after 80-100km is not unusual if you are new to road riding. In time this will be less of a problem as your body gets stronger.
Beware: after 6-12 months of road riding, going back to that lovely single-track will be very scary
Mandatory helmet law?
"An unjustified and unethical imposition on a healthy activity."
Thats pretty much how I have it. Saddle nose is probably a couple of centimeters further back though. Fingers stretch to about 5-6 cm behind the bars.
I'm a bit confused about the bit "when your hands are in the drops behind the brake levers your elbow should be at 90 degrees to where your hands are, not slightly straightened out or tucked back in by you."
Do you mean your elbows should be in line between your shoulders and your hands? My arms are straight whether they are on the drops or the hoods. To get elbows that are bent at 90 degrees on the drops I have to be kissing the bars.
This is a bit misguided I believe. Some years ago when doing a Cycle-on course for teaching staff the guy running the course (might have been Keiran Ryan??) advised that when you have correct position you should observe a 90 degree angle between your upper arm and torso. This would apply whether riding on the drops, on the hoods, or riding a MTB on a flat bar. Greater than 90 deg gives poor support and tires your arms, less than 90 deg is cramped and inefficient use of muscles.
Mandatory helmet law?
"An unjustified and unethical imposition on a healthy activity."
The trouble with buying over the net is that you are certain of no help setting up the bike to your personal body shape.
Here's some further explanation from Colorado Cyclist:
'Unfortunately, there is no formula for sizing the top tube and stem that works as well as the inseam method. One indicator comes from glancing down at the front hub while riding in the drops; your view of the the front hub should be obstructed by the handlebar. LeMond recommends that your elbows, bent at 65-70∞ with your hands in the drops, should be within an inch or two of your knees at the top of your stroke.
Measure your current bike's top tube and stem. Then, decide how you'd like to alter that fit; add the top tube length to the stem length to get your overall top dimension. The very reason we stock stems in 1cm increments, from 7cm to 14cm, is just to let you dial in your best top tube and stem length.'
and another from Peter White Cycles:
'For riders with drop bars, if you place your hands down in the drops at the forward most position, (the point that allows you to easily reach the brake levers), then bend your elbows enough that your forearms are horizontal, your elbow would be at a ninety degree angle for a good starting point. From there, try moving the bar in one half inch increments forward and back to find the best reach for you. Most people are quite comfortable just with the ninety degree elbow position. But that doesn't mean it's right for you. And of course this isn't a position you'd want to spend much time riding in, except on the occasional banzai descent down a mountain pass!'
Both are in the US and informative. Again this is just a guide to begin setting up.
That looks pretty impressive. I've kept a copy for reference.
Oddly enough, this thread is the second hit...
...whatever the road rules, self-preservation is the absolute priority for a cyclist when mixing it with motorised traffic.
London Boy 29/12/2011
I found it on a another forum where there was heated debate on the usefulness of the 'fit calculator'. I prefer this calculator as it focuses on saddle setback and height.
For me the results were very close to the Competitive Cyclist calculator and is alot quicker
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