Flat Bars to Drops - Stem Length / Rise Change?

[simon.r]

I've just been a very silly boy and ordered an On One Macinato frame.

I'm going to build it up with either a Mungo bar or an old WTB drop bar, similar to the Midge. It will, at least initially, be a 'bitsa' build using mostly stuff I have lying around.

I have a Pompino fitted with flat bars and an 80mm / 10 degree stem, which is a perfect fit. AFAIK the Macinato is the same geometry (front end) as a Pompino.

Is there a 'standard' change to stem length / rise to convert a flat bar bike to a drop / moustache bar bike? My gut reaction is that I'll need a higher rise stem?

 

[MacB]

It can be a weird one and just doing some maths doesn't always cut it, to compare different stems this site is excellent:-

http://alex.phred.org/stemchart/Default.aspx

Then it depends on the bars and controls you opt for, some of the moustache style bars sweep forward then back thus placing the grips roughly the same as a falt bar for reach. For various drop and dirt drop bars you need to factor in the forward sweep and where/how you intend to ride them. I've seen drops with sweeps from 50 to 120mm, then add the hoods on and they can be a lot more reach.

The 'accepted' wisdom on dirt drops, ie flared drop bars primarily for offroad(though you don't have to) use is that they should be set for riding in the drops. One guys says that if the tops or hoods are comfy for extended periods then the bars are set up wrong. To get this can be a bit counterintuitive, or even impossible for taller people, I'll try to explain:-

If you switched to regular drops and prioritised the hoods then you would probably want to go to a shorter stem. I believe about 50mm is the sort of difference you'd be looking at.

If you want dirt drops then it's more a case of raising them up and lengthwise you'd want about the same. The theory being you're trying to get the drop part somewhere near where a flat bar would be both for reach and height. Even with bars that have a very shallow drop this can mean a lot of spacers to lift the stem or a very steeply angled stem, quite a few around 35/40 degrees. For example you currently have 80mm at 10 degrees, if you switched to a 130mm at 40 degrees that would give you almost the same reach, at just 3mm less. But it would lift the bars by 73mm which, considering the drops is likely to be around the 80mm mark, may well be about what you'd need. This is if you can't actually raise the stem via spacers, if you can then you can factor in the number of spacers on the link above.

Unfortunately the short answer is some trial and error and maybe an adjustable stem to fine tune.

 

[amaferanga]

Have you tried the Midge-type bars? I tried them on my Pompino, but changed back to drops after a couple of weeks cos they just felt ridiculous. The position was in no way better than drops and they're so wide they just felt wrong. Some love them, some hate them. It's a hate for me.

 

[simon.r]

MacB - thanks very much for that, useful stuff. I'm fairly tall, with my height in my legs rather than my torso. My XL Pompino has 45mm of spacers below the stem. (My saddle is still roughly 150mm higher than my flat bars). Using the 'accepted wisdom' on the dirt drops that would probably mean an additional 20mm of spacers (the maximum, assuming the Macinato fork steerer is the same length as the Pompino) and a steeply angled stem to put the drops somehwhere near the level of my flat bar. That would explain why I've never felt comfy with them when I've had them fitted to other bikes - they would have been far too low.

amaferanga - see above. I've used the Midge type bars but they never felt right, which may have been due to the positioning.

This bike will be used solely for road so I may see if I can pick up a cheap pair of conventional drop bars to have a play with - I've no great desire to use the WTBs, it's just that I have them sat unused in the garage!

"Unfortunately the short answer is some trial and error and maybe an adjustable stem to fine tune."

I figured that would be the answer, but some good info there to give me a starting point. Cheers.

 

[MacB]

Alternate bars have sort of been my thing I've tried a lot and, quite painfully, spent a lot in my experimentation. I'm not going to type it all out here but a search on my posts will give you a lot of data and there are some great threads on the CTC forum as well. For what it's worth my bikes currently sport:-

Road/weekend - Salsa Cowbell 3 splayed drops - 570mm ETT and 110mm stem 0 degree - 200mm head tube
Offroad - On-One Mary Bars - 620mm ETT and 90mm stem 8 degree
Tourer/Commuter/Allrounder - Jones Loop H-Bars - 615mm ETT and 90mm stem at 0 degree - 200mm head tube

Two of these are custom with their 200mm head tubes as I prefer a longer HT than a big stack of spacers. I do know that the On-Ones have pretty short HTs, I didn't keep my Pompetamine frame very long.

I have tried various flat/riser bars, with and without bar ends and those inboard as well as outboard and with a variety of sweep, butterfly bars, Northroad bars, Midge Bars, Salsa Woodchippers, 4 different regular(but shallow) drop bars, cut Loop H-bars, Titec H-bars and moustache bars.

 

[simon.r]

I started to play around with the new frame today. I'm not in a rush to build it, it will be done as and when I have the time and money.

Existing set up on the Pompino:

Macinato with dirt drops (these are 3ttt WB1):

WIth On-One Mungo:

Please ignore the multi-coloured headset spacers, the seat-clamp, etc - it will NOT look like this when it's finished

The saddle is at about the right height. I'd be interested to hear any comments regarding the bars and/or their position.