I have a 2008 Felt B2 with the bayonet fork. I would like to get a new set of aerobars, however many of the new aerobars, like the HED black dog are for 31.8 stems only. The bayonet stems are for 26.0 only. The new devox aerobars that Felt makes look pretty good, but it looks like you have to order through a dealer maybe. Is there any possible way to get a 31.8 stem on the Felts with a bayonet front end?
I’ve used Oval R710 and Dimension Adjustable stem on my 07 DA.
You can get Dimension here or just google Dimension adjustable stem
http://aebike.com/page.cfm?PageID=30&action=details&sku=SM2086
If you have the stem with the set screw, then no, if you have the earlier stem, then I believe you can swap it out as stated above.
If you have the stem with the set screw, then no, if you have the earlier stem, then I believe you can swap it out as stated above.
Actually yes, yes there is, our professional riders on the Garmin/Slipstream and Hawk Relay ProCycling team have been using them for some time. Developed in concert with the latest splined top crown for the new DA and Tk1, the 31.8mm extensions will fit the 2008 Bayonet forks with the set screw (45 spline hinge). Other aftermarket brands are available for stems w/o the set screw (36 spline hinge). These stems are now shipping with Tk1 and DA framekits and are available from your Felt retailers.
Regards,
-SD
Dave,
I imagine the same applies to the 2009 models? I noticed the stem was different between the DA and the B2 so wanted to make sure there wasn’t a difference.
Are you referring to the 3T bar?
Dave,
I imagine the same applies to the 2009 models? I noticed the stem was different between the DA and the B2 so wanted to make sure there wasn’t a difference.
Are you referring to the 3T bar?
The DA and B2 models all use the same 45 spline stem extensions, so yes, the new 31.8mm stems will fit both (and Tk1 as well).
Rgds,
SD
Hi Dave,
I know this is not a triathlon question, and sorry for hijacking, but speaking of the bayonet and the TK1:
I’m looking into getting a new track bike and I was wondering about traditional geometry and the bayonet steering system. With a 90mm stem in place, for example, would that 90mm be measured from the steer tube center to the center of the handlebar (as on traditional, non-bayonet steering) or is that 90mm measured from the “hinge” to the handle bar center? It looks as if the hinge is a few cm in front of the actual steer tube axis, and if a 90mm stem is measured from hinge to handlebar, this would translate to an equivalently longer stem relative to a non- bayonet bike.
Conversely, the top tube on a small TK1 is listed as 530. Is that measured from seat tube center to steer tube (head tube) center, or is the measurement extended to the hinge?
My current road setup has a 527 top tube with a 120 mm stem (which could probably be about a cm shorter.) I was just wondering if the bayonet would throw my reach too far out, even while using the shortest possible stem extension. I’ve asked a few bike shops, one told me that they’ve had no problems with translating traditional top tube/stem measurements to their tri bikes with the bayonet system, another told me to contact Felt, which I have done. A third shop was no longer a dealer 
Thanks for any info!
I know this is not a triathlon question, and sorry for hijacking, but speaking of the bayonet and the TK1:
I’m looking into getting a new track bike and I was wondering about traditional geometry and the bayonet steering system. With a 90mm stem in place, for example, would that 90mm be measured from the steer tube center to the center of the handlebar (as on traditional, non-bayonet steering) or is that 90mm measured from the “hinge” to the handle bar center? It looks as if the hinge is a few cm in front of the actual steer tube axis, and if a 90mm stem is measured from hinge to handlebar, this would translate to an equivalently longer stem relative to a non- bayonet bike.
Conversely, the top tube on a small TK1 is listed as 530. Is that measured from seat tube center to steer tube (head tube) center, or is the measurement extended to the hinge?
My current road setup has a 527 top tube with a 120 mm stem (which could probably be about a cm shorter.) I was just wondering if the bayonet would throw my reach too far out, even while using the shortest possible stem extension. I’ve asked a few bike shops, one told me that they’ve had no problems with translating traditional top tube/stem measurements to their tri bikes with the bayonet system, another told me to contact Felt, which I have done. A third shop was no longer a dealer
Thanks for any info!
The 90mm stem would be measured from the center of the head tube, where a traditional steerer tube is located. The Tk1 uses a low profile top crown that has the hinge 50mm forward of that steering axis. So to achieve a 90mm effective stem length, you’d need a 40mm extension, which would come with the Tk1 in both 31.8mm and 26.0mm bar bore clamps. The bayonet does not effect the relative position of the top tube measurement or the effective stem length. You should use the geometry chart for the Tk1 the same as any other non-bayonet equipped bike. One of the many advantages is that the stem’s stiffness is enhanced because the effective extension is much shorter, and of course there is no exposed steerer tube so there is ZERO torsional deflection or “give” from the use of headset spacers or other fitting-specific compromises.
Let me know if you have any other questions. I hope this was clear.
-SD
Ah HA!!! Very clear! Thank’s SuperDave!
One more question, and again, sorry for hijacking to the other end of the bike:
I was at the LBS today checking out the Felts and I noticed the aero seatposts on some models are flared or fatter toward the rear top of the post (trailing edge), others are not. The posts that are not flared appear to be able to be “buried” into the frame to achieve a very low seat height. It looks as if the posts with the flared trailing edge toward the top of the post may not be able to get as low, as this slightly wider trailing edge may not fit past the seat clamp.
Do the TK1’s have the wider upper trailing edge on their seatposts, or is it the same profile throughout the entire length of the post? I’m wondering if I can achieve a 61-64cm BB to seat rail distance on a size SM TK1 without any seatpost issues. On a TK2, I would have to opt for a traditional round seatpost because the aero profiled section of the stock post would prevent the saddle from getting as low as I need it.
Thanks again for the info.
Ah HA!!! Very clear! Thank’s SuperDave!
One more question, and again, sorry for hijacking to the other end of the bike:
I was at the LBS today checking out the Felts and I noticed the aero seatposts on some models are flared or fatter toward the rear top of the post (trailing edge), others are not. The posts that are not flared appear to be able to be “buried” into the frame to achieve a very low seat height. It looks as if the posts with the flared trailing edge toward the top of the post may not be able to get as low, as this slightly wider trailing edge may not fit past the seat clamp.
Do the TK1’s have the wider upper trailing edge on their seatposts, or is it the same profile throughout the entire length of the post? I’m wondering if I can achieve a 61-64cm BB to seat rail distance on a size SM TK1 without any seatpost issues. On a TK2, I would have to opt for a traditional round seatpost because the aero profiled section of the stock post would prevent the saddle from getting as low as I need it.
Thanks again for the info.
The Tk1 has a different seatpost altogether. It has a shape that has better charateristics suited to a track bike that is used indoors.
The Tk1 seatpost shape is very long and it is designed to be cut down, like a steerer tube, to suit the rider’s preferred height, although it is adjustable like a conventional seatpost. The “net” shape is the same from the clamp to the bottom, so it can be completely installed in the frame (once cut down short enough) unlike the seatposts you noticed from previous model years.
Remember to check the seat tube height on the Tk1: a 52cm does not have a 52cm (c-c) seat tube. It just “fits” like a 52cm.
-SD
Will the 2009 Felt DA top crown fit a 2007/2008 Felt DA? If so, when will they be available to replace older top crowns that don’t have lateral adjustment?
Will the 2009 Felt DA top crown fit a 2007/2008 Felt DA? If so, when will they be available to replace older top crowns that don’t have lateral adjustment?
The new top crown fits the new Fork, and does not fit with the Bayonet from '07 and '08.
there is a small amount of rotational adjustment on both designs. This can be checked by installing the stem with the two front bolts hand tight, then assembling the rest of the system and moving the top crown back and forth on the steering axis.
The new top crown allows for this adjustment without removing the extension, which speeds and aids the accuracy of this adjustment, but it is not an exclusive to the new design.
-SD
Super Dave,
Is there a video on Felt’s site showing this? Because of the countersink of the 2 bolt hole locations, once the right side bolt is tightened, it throws it right back to being off center.
My top crown is noticeably pointing to the left. I emailed you some pictures of this problem. It isn’t horrible, but noticeable. I wonder if I just have a bad top crown.
BTW, I love this bike.
I have an 09 Da… My LBS just called Felt and said felt only had an 80mm stems available in the 31.6.
Do you know where I can get a 90mm stem or can you tell me the after market one that fits the 09 headset.
I have an 09 Da… My LBS just called Felt and said felt only had an 80mm stems available in the 31.6.
Do you know where I can get a 90mm stem or can you tell me the after market one that fits the 09 headset.
The size you need is 31.8mm bar clamp, not 31.6mm.
The 2009 DA has a top crown with a 50mm effective length, so to get to 90mm, you’ll need the +40mm extension. The “80mm” version should be the size that will work to achieve an effective 90mm extension length. 2008 and 2007 DA has a very different fork assembly, along with a shorter effective top crown and hinge position.
We’ve just finished the update on the installation instructions. You can find them on our website under the “INFO” tab, or directly following this link:
http://feltbicycles.com/09/content.aspx?catid=1540,1539&pageid=1537
-SD
Understood but If I have the Stock Stem(26mm) that has an effective length of “90”…
shouldn’t the oversized version be the same size?
Understood but If I have the Stock Stem(26mm) that has an effective length of “90”…
shouldn’t the oversized version be the same size?
yes. Of course, your arm rests are much more critically important to adjust for fore and aft.
Ok… So at the risk of sounding dense… I’ll go back to my orgininal question. If I wanted to keep the same dimensions as the stock stem… Effective 90mm… Can you tell me where I can get “90” effective length stem for the 31.8 clamp size.
"I have an 09 Da… My LBS just called Felt and said felt only had an 80mm stems available in the 31.6.
Do you know where I can get a 90mm stem or can you tell me the after market one that fits the 09 headset."
Ok… So at the risk of sounding dense… I’ll go back to my orgininal question. If I wanted to keep the same dimensions as the stock stem… Effective 90mm… Can you tell me where I can get “90” effective length stem for the 31.8 clamp size.
"I have an 09 Da… My LBS just called Felt and said felt only had an 80mm stems available in the 31.6.
Do you know where I can get a 90mm stem or can you tell me the after market one that fits the 09 headset."
First off, there is no such thing as a 31.6mm handlebar clamp diameter. The diameter is 31.8mm.
Next, if you are changing base bars, how do you know the handlebar position will be exactly the same?
Lastly, there is no such thing as an 80mm stem for a 2009 DA with a 31.8mm clamp diameter. If it was etched with 80mm or described 80mm, that dimension would only be accurate for a 2007 and 2008 DA as the fork/stem on those models is a different shape resulting in a net length of 80mm, not a net length of 90mm.
Lastly, even if you end up +/- 1cm on a totally new base bar, couldn’t you position your arm rests and extensions in the same place as they are (were) on the 26.0mm size?
-SD
p.s. slowtwitch is probably not the easiest medium to communicate what I am trying to say, feel free to call me if you have a minute.
SD,
I have a Felt DA, black with the gold accenting. I presume this is an '08 model. If so, where can I get the compatible 31.8 stems for the bayonet fork?
thanks
ER