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mmmBop Stem Length
 

[Closed] mmmBop Stem Length

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[#1725183]

Currently have a 90mm 5deg stem on my mmmBop and I think I'd like to get a shorter one. Although the bike handles great, at the moment with the slack(ish) head angle and 130mm forks the steering feels just a little bit heavy/sluggish and not as nimble as I think it could.

I know the recommended length is 50-70mm so that's a good starting range, but I'm not sure how short to go. At the moment the length of the bike feels perfect (18in frame with an inline post) I'm concerned that a shorter stem will make me feel cramped. I could get a lay-back post too, but then I'm concerned that the front end will feel too light as it already feels really nicely weighted and easy to lift/manual and I don't think I need any more rear wheel traction.

Have any other mmmBop owners experimented with different stem lengths, how did you get on?


 
Posted : 21/06/2010 2:00 pm
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How wide are your bars? If you can beg/steal/buy a cheap one to try out, that would probably be ideal. Then you can flog it and get a better one.


 
Posted : 21/06/2010 2:05 pm
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I have a flat 50mm stem on mine with 710mm hi-rise bars, layback post with saddle quite forward, 6 feet tall on 18" frame

Feels OK to me, ran this on a BP too


 
Posted : 21/06/2010 2:07 pm
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Bars are pretty wide: 710mm hi-rise - that would certainly slow down the steering compared to narrower bars, but its more the weight than the speed I'd like to change.


 
Posted : 21/06/2010 2:14 pm
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Not sure I follow, the weight of what?


 
Posted : 21/06/2010 2:32 pm
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The steering weight is how hard it is to move the bars, the steering speed is how quickly you can move the bars, there's a subtle difference.

Generally my understanding is the bar width generally impacts the weight of the steering (longer bar = more leverage = less weight) whereas the stem length changes the speed (shorter stem = less steering arc = more speed). However a change to one will impact the other slightly.


 
Posted : 21/06/2010 2:45 pm
 wors
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recommended length is 50-70mm

there is your answer.


 
Posted : 21/06/2010 2:58 pm
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I had a 70mm on mine with low rise 710mm bars and it was perfect.


 
Posted : 21/06/2010 3:00 pm
 ojom
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However a change to one will impact the other slightly.

I think you are making too much of a meal of it.

Go out and razz it. Forget about steering weight - have a beer to take your mind off it.


 
Posted : 21/06/2010 3:01 pm
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If you are happy with your bike in every other respect, i'd try 70mm. Changing from 90 to 70 is still a fairly big jump, and should have a noticeable effect. If you can get a cheap stem to try that's probably still the best idea IMO.

The Ragleys were designed with in-line posts in mind, so i'd avoid using a layback to start with.


 
Posted : 21/06/2010 3:03 pm
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The Ragleys were designed with in-line posts in mind, so i'd avoid using a layback to start with.

Which is a bit odd considering the only Ragley seatpost has layback


 
Posted : 21/06/2010 8:19 pm
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Which is a bit odd considering the only Ragley seatpost has layback

Yes, I know. Not sure how that happened. Nice post though!

We have an inline one coming 🙂


 
Posted : 21/06/2010 8:37 pm
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I run a 70mm thomson zero rise with 710mm bars and its super, makes me wish i hadn't spent £2k on a full susser!


 
Posted : 09/07/2010 9:33 pm
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Anyone tried any of the wide flat bars on their mmmbop? Getting the bits together for a build and considering something like the sunline v1 flat. Thinking they would work well with the 160 lyriks. Bit worried about it fouling the top tube though.


 
Posted : 03/11/2010 12:36 pm
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Low rise 685mm Eastons, 10mm spacer under stem, brake levers hit top tube when bars turned.
Just don't crash or do bar spins.


 
Posted : 03/11/2010 12:42 pm
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I am using layback post (joplin_ with the seat forwards (would be central on an inline post) and a 50mm stem with 710mm wide bars.

6ft2 on an 18" frame


 
Posted : 03/11/2010 12:46 pm