Sizing a bike.

[David Garside]

Hello. I've had a quick look around the forum and cannot find an answer to this question...I apologise if there is one and i've not found it.
How do you actually size the bike up that you require...I'm 5'6" and have an inside leg of 31". I know there is a relation to the distance "bum to pedal and bum to floor"....but how and what do you do to get the correct one for you.
Sorry if this seems a very basic and stupid question. ​

 

[dharma66]

It seems to me ( though I have little experience) that the best approach is to visit a bike shop and try them on for size, especially if you don't have a lot of recent experience of bikes and the different manufacturers.

For example, if you took my inside leg/height measurement, I'd be sized up for a 17.5" frame for a Trek hybrid. However, when I straddled one at my local shop, the assistant (who is way more knowledgable for me) immediately suggested I try a 20". On this size frame I have only a small amount of top tube clearance, but on the smaller frame, my knees felt like they were bumping the handlebars, and the whole thing felt very cramped.

If I'd followed simple sizing guides and bought online without trying for size, I'd have been in a bit of mess.

 

[David Garside]

Thank you for that...maybe that's what i'll do then. I'm ok at the moment with what i've got but if I decide to go the whole hog and get a decent replacement i'll need the right advice. I'll take yours and visit the nearest (proper) local dealer.
Thanks again.

 

[Pauluk]

David, out of interest are you looking at getting a road, hybrid or mountain bike?

 

[David Garside]

Hmm ! That's the age old question. I'd like to do a bit of road and trail so I suppose a hybrid is the answer to that....I don't want to do anything really rough but mainly old tracks, canal towpaths, old railway tracks etc. What would you suggest for those uses ?.

 

[Pauluk]

That's similar to what i do and I use a hybrid, but I suppose you could use anything that takes your fancy. I use a hybrid as its a bit more flexible/go anywhere and I don't need/want road speed particularly. Although having said that I wouldn't mind having a road bike as well. I have a couple of mountain bikes but don't use them any more.

Hybrids a good choice for me as they have 700mm wheels and the rims tend to take a good range of tyre widths, so you can have thin tyres for road work or go for a thicker/more treaded tyre for off road, or a compromise between the two. They are also good for fitting racks and panniers but then again so are other types of bikes.

I suppose hybrids are a jack of all trades master of none, but I'm not a master cyclist anyway.

The reason I asked the question was that if you were planning to do some serious mountain riding then I believe sizing is a bit different in terms of where you want the top tube as this needs to be quite low for this kind of riding.

It seems to me ( though I have little experience) that the best approach is to visit a bike shop and try them on for size, especially if you don't have a lot of recent experience of bikes and the different manufacturers.

I would definitely agree with this 100 per cent

 

[vickster]

Pick a few you like the look of within your price range and go to your local bike shop with stock. Manufacturers vary in geometries, as do ranges from the same manufacturer, and not least they call them different things - by size, S/M/L etc and even then these vary! Reach is key as much as height or leg length

Any good shop should let you sit the bikes, adjust as needed etc

 

[David Garside]

Brilliant! Thank you everyone for your help and support. I think the hybrid sounds ideal...I'm not a serious cyclist but just want a bit of off road experience as well as on road for commuting to shops etc. I don't want to go serious mountain riding or downhill or anything like that.
Once i've got back into it a bit more and i'm sure I'm going to get the use of it, i'll definitely go down that path.
Thanks again everyone...and for a fantastic forum.