My Black Mountain Cycles Road+

[Tom]

Well, after putting off the fender installation for a *long* time (i.e., 2+ years, although I was overseas for a good chunk of that time), I finally got my 59cm BMC Road+ completely finished--although it probably deserves better bottle cages. I had some concern before buying it that it wouldn't fit me well because I typically ride a 65-68cm road bike, but Mike at BMC assured me that it would--said he's built just like me with long legs. He was right--it fits great. It's a great ride, too. 

Tom   

[Pat Smith]

Looks great! Racked up many miles on my Road+, though I decided it did not handle well with a front random bag so I've switched to a half free bag and saddle bag instead. Also put 700 x 32mm tires on, as it's my only "road" bike. Enjoy!

Pat

[John P]

What are the widest 700c tires you think would fit on a Road+?

  -John

--
You received this message because you are subscribed to the Google Groups "650b" group.
To unsubscribe from this group and stop receiving emails from it, send an email to 650b+uns...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/650b/b72e4f50-b27a-4b28-971d-f8254ba52895n%40googlegroups.com.

[Patrick B. Smith]

My 32mm gravel kings have tons of room. At least 35 maybe 38. 

[Michael Mann]

When I got my Road+ a couple years ago (Rubystone Red!) I had a couple email exchanges with Mike V and 700c tire size was one topic. My recollection was 700 x 38 will probably fit fine. But he also seemed indifferent to that use, which I get. Once you’re asking “how wide?” With 700s, the answer is “wider if you run 650b.”

That said, I’m ready to build a 700c wheel set for mine - I’ve been waiting over a year for a DT Swiss 350 12x142
Center lock rear hub on QBP and they finally came in stock. Rims will be DT Swiss RR 421, and I’ll run 700x32 Gravelkings.

Mike M

Sent from my iPhone

On May 19, 2022, at 8:23 AM, Patrick B. Smith <pbsm...@gmail.com> wrote:



To view this discussion on the web visit https://groups.google.com/d/msgid/650b/CA%2ByZinUiz%3DjTroK5d15dUErfOrB9Gz4FWXMR5ffBDmNNMEzcBA%40mail.gmail.com.

[nlerner]

I've fitted my BMC Road + with 700 x 38mm tires with no problems.

Neal Lerner

Brookline MA

[John P]

You all rock.  Thanks much!

  -John

[dgm...@gmail.com]

I just got mine, after having it sent to Bilenky for couplers.  Loving the ride, but  having issues that I'm wondering if other owners are experiencing.  I'm running mine with 700cx32, and find that when the road surface is right, I get flexing of the fork that causes the front end to bounce around fairly severely and you can see the blades moving back and forth  fairly considerably.  Bad enough that I've been through 1 set of headset races in about 6 months.  I was wondering if it was just a combo of pads and rotor, so pulled the Shimano pads and replaced with a different mfg, after cleaning the rotor.  The problem still is there, but maybe a bit less.   

[Patrick B. Smith]

Every once in a while I get it too. I'm running cable actuated brakes so they don't have that great of stopping power. Never bad enough it's damaged bearings. I've got close to 6k miles on mine. 

The fork blades on my other bike, a Jamis Aurora Elite, are very flexy. They clearly just took the rim brake fork and added mounts for discs (it's from 2010). That fork flexes so much that when you stand to pedal the rotor starts rubbing on the pad. It's only got BB7 brakes that don't grip so well, so not quite the same problem you describe. 

--
You received this message because you are subscribed to a topic in the Google Groups "650b" group.
To unsubscribe from this topic, visit https://groups.google.com/d/topic/650b/m_Q7on8G_TU/unsubscribe.
To unsubscribe from this group and all its topics, send an email to 650b+uns...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/650b/6d91dd0e-2156-4edf-ae50-3c2c587dda8an%40googlegroups.com.

[dgm...@gmail.com]

Thanks for the response.  Hoping to figure it out, as I just can't get quite comfortable on this bike with it happening unpredictibly.  And I love my old monster cross an the geometry works well for me otherwise.

[Jeff Bertolet in Raleigh, NC]

To clarify: 

While braking on certain surfaces, the fork legs are moving around a lot. It seems like you are saying the brake is shuddering or juddering. The pads are not engaging the rotor evenly? 

I have seen this occasionally on some cable/actuated calipers. I have not seen it yet on hydraulics. I think you are on the right track as far as trying new pads.

For cleaning contaminated rotors (and using new brake pads), I have had 100% success with 1. cleaning with industrial degreaser (we use OzzyJuice at work, maybe carb cleaner would also work). 2. Thorough rinsing 3. Heat with heat gun or flame to ~4-500 degrees. 

[William Lindsay]

dgmoeny said "I just can't get quite comfortable on this bike with it happening unpredictibly."

Is it so unpredictable that you don't know how to make it happen?  Or do you have a pretty good idea how to make it happen?  If you have a good way to force it to happen, then that can serve as your test case to see if you've solved it.  

I've experienced a similar phenomenon with my Black Mountain La Cabra, which has drop bars, full hydraulic disc brakes and a straight legged non-suspension fork.  Under very hard braking, and hard dirt trail conditions, I have experienced the front fork semi-violently wobbling front to back.  What I think is happening is that the braking forces flex the fork BACKWARDS, which flexes the fork DOWN into the dirt.  When traction just gives way, the front wheel unflexes FORWARD, which unflexes UP and the tire loses most of it's contact with the ground and the fork unloads all the way forward and up.  Now my weight plants the front wheel back on the ground and the front wheel is locked at that moment, which loads up the system again.  With no changes to this resonant system, it'll just cycle over and over, maybe 6-8 times per second.  

Does this sound like what is happening with you?  If so, I don't think it has anything directly to do with brake pads per se.  It has to do with the fact that you are braking hard with comparatively low traction tires.  My "solution" on my La Cabra is two fold.  I increased traction with lower air pressure, and I now use the bike in an area of the country where the trail are not as hard.  Behaviorally, if I get that onset of resonance, I blame it on braking too hard and I let off the front brake slightly -OR- I try to improve front traction by a careful weight shift forward, pushing harder into the front tire so it doesn't let go.  

If you aren't sure whether this is what's going on, the experiment I would recommend would be:

-go out and make it happen a few times.  

-swap out the front tire to a much wider one, at a lower pressure. 

-try to make it happen again

If you fail to make it happen with a wider tire, then that would suggest that it's too much front braking for the comparatively small amount of front traction.  

I suspect it's possible that a far stiffer fork could also make it a lot harder to force this situation, but that's a much more expensive experiment.  

In a very hand-wavy way, I could argue that experimenting with rotor diameter could change the dynamics, but that's just a guess.  

Bill Lindsay

El Cerrito, CA

[dgm...@gmail.com]

Bill-

That's exactly what is happening.  It's certainly better with different pads and a freshly cleaned rotor, but not gone away.  I may also have started modifying how I ride.  My suspicion is not so much blade flex, but flex in the actual steerer... still gets us to the same point either way.  This is primarily a road bike for me, but I'll swap out for a pair of 650x42s at some point and see how things go.