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80mm stem= bike doesnt fit?(12 posts)

80mm stem= bike doesnt fit?David Ho
Jan 11, 2002 7:30 PM
I have a Giant compact frame and I am currently running a 90mm stem, but I want to get a little closer.Will a 80mm Salsa stem be too short? I mean if I have to use an 80 mm stem should I just get another frame and sell this one or can the geometry stand me using this stem and then the bike will fit?I like this bike but fit has been an issue-please lets not open that can of worms!!

Thanks David
re: 80mm stem= bike doesnt fit?dsc
Jan 11, 2002 7:42 PM
Hi David,

Before going to a 80mm stem, how about trying some bars with a shorter reach? Or another 90mm stem with a slightly greater rise (if you're not one of those people opposed to 'that look' :-)) Or a combination of both. All of these ideas will bring you 'a little closer' (and slightly more upright), without having to go to a shorter stem.

-Debi
I agreeDave Hickey
Jan 12, 2002 7:43 AM
You can gain alot more with shorter reach bars. What bars are on your bike now?
re: 80mm stem= bike doesnt fit?dbo
Jan 11, 2002 10:36 PM
I'm guessing you already have a straight up seat post and not a post with a setback?
Thomson post-saddle totally forward nmDavid Ho
Jan 12, 2002 6:20 AM
nm
Sell it!jtolleson
Jan 12, 2002 9:43 AM
Unless you have abnormally short femurs, your saddle probably shouldn't be all the way forward without risking KOP. If you've shifted your saddle because of a problem with effective top tube length, then your bike doesn't fit.

Especially now that you are thinking about an 80 stem.

No criticism here. I just started a thread a month ago about finally deciding my LS was too large (especially in the tt) and I'm running a 90 stem with a little rise in it.
too little info....C-40
Jan 12, 2002 3:42 PM
There is nothing "wrong" with using an 80mm stem, but as others have suggested, a short reach bar would be another option that would produce the same result. Also take a look at your brake lever position. Moving the levers up on the curve also moves them back, producing a shorter reach. Look at pictures of euro-pro bikes. Most of the levers are positioned quite high.

I would ignore all other advice until you read up on what constitutes a proper fit. You have not posted enough information for anyone to make any valid recommendation. Even with valid inseam and height measurments, there are too many variables to determine an appropriate stem length.

You should really ignore the advice about changes to your seatpost and saddle position. These adjustments are not for the purpose of changing the reach to the bars.

There are a lot of websites where you can learn about KOP and many other aspects of bike fitting. Try some of the following and post again with more specific info. If you do end up buying a different frame, you need to determine the appropriate geometry to avoid a repeat of your current problem.

cyfacusa.com
coloradocyclist.com
sheldonbrown.com
peterwhitecycles.com
Ok, OK heres my info for youDavid Ho
Jan 12, 2002 7:56 PM
I bought thif compact frame 2 months ago after coming off a 56 cm steel bike.This frame is a large. I had my previous bike fit kitted and had my measurements from that.My saddle height is perfect and the distance from the nose of saddle to bar is the same but it doesnt feel as close as I would like.Maybe it is the shorter headtube length putting the bars a little lower?Hope this helps!
better, but more needed...C-40
Jan 13, 2002 6:00 AM
The large giant has a 58.5cm TT with a 73 degree seat tube angle (STA). Giant does not list the head tube length on their website.

If I knew the brand of your steel frame, the geometry might be obtainable. A 56cm (center to top?) frame would typically have a 55-56cm top tube length if it also has a 73 degree STA. The giant's top tube is probably 2-3cm longer than top tube of your old frame. The head tube on a 56 would typically be 140mm in length, plus about 37mm for a threadless headset (almost 7 inches total length). How does the the length of the giant's head tube and headset compare?

It sounds like a medium size giant would have been more approriate, unless were using a very long stem on the 56cm steel frame and wanted to reduce the stem length. This doesn't appear to be the case.

When buying a new frame, a close comparison of your current bike's geometry should always be made. This is particulary true with frames like giants that are only available in three sizes. IMO, the three sizes will leave a lot of people with a poorly fitting bike.

All of the critical geometry (head tube length, top tube length and seat tube angle are easily measured on a existing bike. If a shop sold you this frame without measuring your old bike, shame on them.
Saddle fore-aftjtolleson
Jan 13, 2002 11:52 AM
Should NOT be done by deciding how close you want to nose of the saddle to the bars. Just because you've got your saddle the same distance from the bars as it was on your old bike doesn't mean your saddle is the right place.

I'm saying now based on this latest disclosure that you really need to cough up the $50 or so for a professional fit kit with this bike. Get your saddle fore-aft right FIRST and then you can better evaluate your reach.
How would we know?Kerry Irons
Jan 12, 2002 4:09 PM
I would say that an 80mm stem might be fine for someone who is 5'4", but would be way short for someone 6'4". Since you didn't even bother to tell us your frame size, let alone your physical dimensions and how you have the bike set up, your question is about like saying "Are size 46 shoes too big?" without giving your regular shoe size.
We wouldn't...TJeanloz
Jan 13, 2002 1:18 PM
Except for C-40, who will get on his sizing high horse and tell everybody exactly what size bike they should be riding.

In general is an 80mm stem o.k.? Yes. It is o.k.- but not typically ideal. When I'd size people at the shop, the target was for a stem in the 9cm-13cm range, with 8cm and 14cm being acceptable but not ideal, and shorter than 8 being possible, but not ideal. Some people will need an 8 or even a 6cm (Salsa makes one) to fit properly on the correct size frame.

Other information that you've subsequently given might lead us to believe that the frame is too large- but it is impossible to be fit in an online forum. Repeat that to yourself: it is impossible to be fit in an online forum.

Contrary to what others might say (C40), it is very, very likely that your Large Giant could be set up with EXACTLY the same dimensions as your old bike.