Go Back  Bike Forums > Bike Forums > Bicycle Mechanics
Reload this Page >

defunkifying diacompe brs101's with tektro levers.

Notices
Bicycle Mechanics Broken bottom bracket? Tacoed wheel? If you're having problems with your bicycle, or just need help fixing a flat, drop in here for the latest on bicycle mechanics & bicycle maintenance.

defunkifying diacompe brs101's with tektro levers.

Old 10-08-10, 07:01 AM
  #1  
Senior Member
Thread Starter
 
Join Date: Sep 2010
Location: frederick, md
Posts: 207
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
defunkifying diacompe brs101's with tektro levers.

hey all-

i have a query.. i've been outa bikes for quite some time (and certainly since before tektro seems to've taken over the brake world!)-- and having recently purchased a new bike with DC brs101s and tektro aero levers.. i'm a little flummoxed.

the response out of the pairing of these things is kinda... well... uninspired. it's just downright UNsnappy and kinda mushy, to tell the truth. dual pivots weren't really around when i was racing back in the mid to late 80s.. so i'm thinking either it's just me, and i haven't figured the magic bullet yet, or they're just kinda inherently that way.

i tried disassembly and reassembly having greased all pivots. helps, but still not so hot. typically i run my brakes super snug-- and they're even WORSE feeling that way (i'm assuming due to weak-ish springs)- so i slacked the response so they'd have more spring travel. still a distinct 'meh'.

IS there a way to beef up spring response out of the pair of these so they snap rather than kinda lazing on and off with NO distinct response? two mechanic friends of mine say 'nay'-- particularly with the campy copy plastic tektro aeros and that it's idiosyncratic of them due to the squish bodies. i wonder if we all just missed some trick?

help!
shorthanded is offline  
Old 10-08-10, 05:22 PM
  #2  
Senior Member
 
Join Date: Aug 2007
Location: NorCal
Posts: 546

Bikes: 2009 Surly Cross Check Frankenbike

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 2 Times in 2 Posts
I have some Shimano aero levers, alloy bodies on those. Yours for $30 with shipping in the US. Left one has some very minor damage on the grey plastic around the lever opening. PM me if you want them.

But, is it possible you have some friction in cables/housing?
Al Criner is offline  
Old 10-08-10, 06:47 PM
  #3  
Senior Member
Thread Starter
 
Join Date: Sep 2010
Location: frederick, md
Posts: 207
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by Al Criner
I have some Shimano aero levers, alloy bodies on those. Yours for $30 with shipping in the US. Left one has some very minor damage on the grey plastic around the lever opening. PM me if you want them.

But, is it possible you have some friction in cables/housing?

thanks for the offer al-- but i think i'm gonna debug first best i can-- mebbe when i get to the bottom of this!

i suppose it's possible there's friction in the cables- but it's present both front AND back, and there's no excessive housing to speak of. i built the bike myself from the factory (it's a masi speciale randonneur)-- so i figure i accounted for that, and nothing SEEMED too long. worth a look again though. i DIDN'T pull the cable and reroute having greased everything.. but i wouldn't figure they needed it nowadays with smooth cabling and teflon lined housing!

hrm... anybody else? thanks al!
shorthanded is offline  
Old 10-08-10, 06:58 PM
  #4  
Senior Member
 
Join Date: Sep 2004
Location: boston, ma
Posts: 2,896
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Likes: 0
Liked 1 Time in 1 Post
turn the "centering screw" clockwise to increase spring tension. make sure pads hit the rims squarely. housing ends should be finished on a grinder or with a file and be capped with a ferrule
reptilezs is offline  
Old 10-09-10, 05:57 AM
  #5  
Senior Member
Thread Starter
 
Join Date: Sep 2010
Location: frederick, md
Posts: 207
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by reptilezs
turn the "centering screw" clockwise to increase spring tension. make sure pads hit the rims squarely. housing ends should be finished on a grinder or with a file and be capped with a ferrule
yeah-- the first thing i did was to slack up the cabling and crank the tension screw as close as comfortably possible to still get my tires out of the thing when i threw the quick release on the lever and the brake and could still yank a 32mm tire out. i might just need to snug it up tighter so i may have to deflate my tires to pull them.. pads are adjusted well, and i didn't pull the ferrules to make sure they're ground-- but its a thought. would a cockeyed ferrule cause that much slop though?

good thoughts-- i'll dog that down today and see. i've thought it was a little strange that the rear brake won't even pull the cable taut between braze-on guides along the top tube-- but it has donuts. hrmph.. i'll have a look-- thanks!
shorthanded is offline  
Old 10-09-10, 06:14 AM
  #6  
Senior Member
 
Join Date: Sep 2004
Location: boston, ma
Posts: 2,896
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by shorthanded
yeah-- the first thing i did was to slack up the cabling and crank the tension screw as close as comfortably possible to still get my tires out of the thing when i threw the quick release on the lever and the brake and could still yank a 32mm tire out. i might just need to snug it up tighter so i may have to deflate my tires to pull them.. pads are adjusted well, and i didn't pull the ferrules to make sure they're ground-- but its a thought. would a cockeyed ferrule cause that much slop though?

good thoughts-- i'll dog that down today and see. i've thought it was a little strange that the rear brake won't even pull the cable taut between braze-on guides along the top tube-- but it has donuts. hrmph.. i'll have a look-- thanks!
with unfinished brake housing the coil housing tends to bend inward and obstruct the cable from moving freely.
reptilezs is offline  
Old 10-09-10, 03:08 PM
  #7  
Senior Member
 
DannoXYZ's Avatar
 
Join Date: Jul 2005
Location: Saratoga, CA
Posts: 11,736
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 109 Post(s)
Liked 9 Times in 6 Posts
Also the mechanical-leverage of the hands are best with more-closed fingers. Having your brakes too tight makes you squeeze with an open hand and you don't get as much force out of them compared to when they are more closed. You get best clamping force out of brakes when you set them up so the levers almost barely bottom out against the handlebars as they're just about to lock up and/or send you over the bars.
DannoXYZ is offline  
Old 10-10-10, 04:54 AM
  #8  
Senior Member
Thread Starter
 
Join Date: Sep 2010
Location: frederick, md
Posts: 207
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by DannoXYZ
Also the mechanical-leverage of the hands are best with more-closed fingers. Having your brakes too tight makes you squeeze with an open hand and you don't get as much force out of them compared to when they are more closed. You get best clamping force out of brakes when you set them up so the levers almost barely bottom out against the handlebars as they're just about to lock up and/or send you over the bars.
yeah-- that i know to be true. my issue though isn't with stopping power though, honestly- they'll stop, for sure. it's more of a modulation/feel issue with the damn things-- which, granted, is TOTALLY preference, and not a matter of function. i tried that angle of backing way off and letting them have lots of breathing room on the rim too-- and it DOES work, it just has a crappy sorta 'cheap' feel about it.. and my guess is that i should go with a more traditional lever/ brakeset- as the 'one sided' spring feels pretty much like... well.. half the springback of a single pivot brake.. go figure, right? i guess the dual pivots are supposed to be 'easier to center' (although i never had any problem centering my single pivots...ever..)-- but the feel is WAAAY different, and that's the main beef. the mechanical advantage thing totally makes sense-- and thanks for throwing it out there, cause it's certainly truth-- but man, it just reminds me of a clunky old ross with safety levers to set brakes up like that
shorthanded is offline  
Old 10-10-10, 10:49 PM
  #9  
Senior Member
 
DannoXYZ's Avatar
 
Join Date: Jul 2005
Location: Saratoga, CA
Posts: 11,736
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 109 Post(s)
Liked 9 Times in 6 Posts
Very odd. Typically in cases like this, I completely disassemble the system and test each component individually:


1. squeeze the brake-caliper closed by hand, does the spring feel strong and does it spring open the brake fully?

2. unclip the spring from the brakes and close & open the arms manually. Does it move smoothly without binding? Is there any axial-play of the arms up & down the brake pivot-bolts?

3. move the levers open & closed, is it smooth? Is there any axial play in the lever at the pivot?

4. coil the brake-cable into a loop end-to-end. Floss the cable in and out of the housing, is it smooth with little force needed?


Usually this pinpoints one or more problem areas. I've found issues with cable-housings where the cut-ends aren't square and they rub on the inner wire. Or they've been stretched. This increases the gap between the housing coils and it acts as a spring. You end up having to compress the housing before the brakes will grab. This adds some sponginess to the feel.

BTW - which Tektro levers are these?
DannoXYZ is offline  
Old 10-11-10, 07:57 AM
  #10  
Senior Member
 
Join Date: Jun 2010
Location: Pearland, Texas
Posts: 7,579

Bikes: Cannondale, Trek, Raleigh, Santana

Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 308 Post(s)
Liked 3 Times in 3 Posts
shorthanded, It may simply be the two brands aren't 100% compatible. I recently did a parts bin mini rebuild on my old Cannondale using Suntour GPX aero brake levers and the already mounted Shimano 600 dual pivot brake calipers. The brakes just aren't as powerful as before with the 600 brifters and I think the culprit is the lever pull isn't at quite the right ratio for the calipers. On another bike I have 105 aero levers working with 105 dual pivot calipers and I can pull stoppies with it.

Brad
bradtx is offline  
Old 10-11-10, 11:44 AM
  #11  
Senior Member
 
BCRider's Avatar
 
Join Date: Mar 2008
Location: The 'Wack, BC, Canada
Posts: 5,556

Bikes: Norco (2), Miyata, Canondale, Soma, Redline

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 44 Post(s)
Liked 45 Times in 35 Posts
The dual pivots gain some of their increase in braking force for the same lever pull over the single pivots by lengthening the distance between the cable pull point and the pivots. But as you're finding along with that increase in leverage ratio comes some spongy system feel. The way to restore as much of a nice solid feel to the levers as you can get is to use premium housing and calbes and to dress the cut ends nice and flat before pushing into the lever or slipping on the ferrule ends as appropriate. Along with this on a road bike with buried cables it is essential to really jam the housings into the receiving seats of the levers and hold that pressure with one hand as you bind the housings to the bars with the other hand. If that step is not done well then the housing will not be tight at this point and you'll feel it as a constant source of sponginess in the lever because you are pulling the housing into the lever each time against the flexible resistance of the foam tape and the housing securing tapes.

Other than this use the usual tricks of the trade to ensure as good a cable system as you can. IE; fresh premium housings, smooth drawn cables, run them dry, dress the ends clean and square and flare the opening with a tapered awl. And if working with older housing and cables ensure that the cables don't have a bad kink at some point inside the housing and if the housings are older suspect that the cable has worn a groove that grabs the cable. If you have either of these last two replace housings and/or cable. Certainly these steps were enough in my cases to enjoy my dual pivot calipers in all cases.

Now if that Tektro lever has some issues that's a whole other situation. How does it feel with no cable in the lever? Try running a cable into it and see if it is still free moving and snappy. Then add a housing. Perhaps as these things go into place one or more of them produce a situation where the cable is dragging over something that could be lubed or lightly dressed away with some work to give a more direct cable pull? I haven't seen these actual levers so all I can suggest is to study how they operate with this sort of option in mind. And if you find that the cable tension is distorting the housing and it is that which is making the feel poor then you have to decide on getting something different or not.
BCRider is offline  
Old 10-12-10, 05:24 AM
  #12  
Senior Member
Thread Starter
 
Join Date: Sep 2010
Location: frederick, md
Posts: 207
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
thanks BC, danno, and brad!

to answer the question-- i'm not sure if they're the 100 or 200 levers... whichever is for a regular dual pivot road brakeset? to aggravate matters-- i'm using them at the far end of the brakearms as well to accomodate 45mm fenders, which i know doesn't help.. but i didn't choose them-- they came on the bike!

danno--- i did disassemble the entire front assembly and do what you asked-- all worked pretty much flawlessly once it was fully greased. no major hangups (but for my own demands of snappy action )-- actuation was fine, lever was fine.. and from what i could tell-- no drag on the housing. it DOES have unsavory slop at the quick release though, which i couldn't dial out.. it's some sort of floating pivot, which i can see would cause some shizzy mush.. but it's there for a reason, i suspect, although i dunno WHY you would introduce that sorta motion in a brakeset.

well crap.. it looks like i'm probably gonna have to give the full system disassembly a go and see if i can take out all the slop in the system one pinch point at a time. i was actually pretty surprised to see that there wasn't a single spot of any lubricant in the FRONT brake, which i did disassemble in vain hope of figuring out the slop. i consequently put it together regreased-- and improved... but i didn't grind all my housings. they're all still fresh from the factory-- but i wouldn't suspect that you always get the custom treatment on ferrule ends from the cats in taiwanese factories.. and i built the thing-- so that would be MY fault .

y'know-- i actually had my hands on a couple of other cats' DP brakes this weekend (first biggish club ride in FOREVER)-- and mine didn't feel bad by comparison. i think it's just an old dudes expectations of serious snap. regardless-- i'm going back in and rebuilding the system again, and if it doesn't get better... i have me an upgrade path to follow.. besidedly-- i could use a bit more clearance for my fenders anyhow. mebbe i could convince the wife i need some paul racers?

thank you gents-- between this and lacing a new set of wheels this week.. i got my work cut out for me!
shorthanded is offline  
Old 10-13-10, 12:08 PM
  #13  
Zip tie Karen
 
Phil_gretz's Avatar
 
Join Date: Aug 2009
Location: Fair Oaks Ranch, TX
Posts: 7,006

Bikes: '13 Motobecane Fantom29 HT, '16 Motobecane Turino Pro Disc, '18 Velobuild VB-R-022, '21 Tsunami SNM-100

Mentioned: 26 Post(s)
Tagged: 0 Thread(s)
Quoted: 1465 Post(s)
Liked 1,542 Times in 806 Posts
Tektro Levers

Originally Posted by BCRider
Now if that Tektro lever has some issues that's a whole other situation. How does it feel with no cable in the lever? Try running a cable into it and see if it is still free moving and snappy. Then add a housing. Perhaps as these things go into place one or more of them produce a situation where the cable is dragging over something that could be lubed or lightly dressed away with some work to give a more direct cable pull? I haven't seen these actual levers so all I can suggest is to study how they operate with this sort of option in mind. And if you find that the cable tension is distorting the housing and it is that which is making the feel poor then you have to decide on getting something different or not.
You've received some excellent troubleshooting advice so far. I wanted to chime in on the Tektro levers. I've used both the R100 (short reach) levers on my wife's bike and the R200 levers on two of my bikes. Of these, we've had Tektro long-reach dual pivots, older Dia Compe cantilevers, and older DiaCompe side pulls. The levers had plenty of pull for good strength for stopping for every type, give good modulation, and contribute plenty of spring back "snap" with their own internal springs added to the caliper springs. So, if the levers are new and not worn internally (the quote above is a good one), I'd say that your problem is not in the levers themselves.

I like the suggestions that the cable housing is not seated properly and moving each time as a contributing factor. It may be that your housing diameter is mismatched (slightly too large with the vinyl covering) to the notches in the lever entry point? Maybe snug enough for threading and assembling the levers and housings, but not snug enough to resist the brake activation without moving?

Good luck. PG
Phil_gretz is offline  
Old 10-13-10, 12:48 PM
  #14  
Senior Member
 
DannoXYZ's Avatar
 
Join Date: Jul 2005
Location: Saratoga, CA
Posts: 11,736
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 109 Post(s)
Liked 9 Times in 6 Posts
Originally Posted by shorthanded
danno--- i did disassemble the entire front assembly and do what you asked-- all worked pretty much flawlessly once it was fully greased. no major hangups (but for my own demands of snappy action )-- actuation was fine, lever was fine.. and from what i could tell-- no drag on the housing. it DOES have unsavory slop at the quick release though, which i couldn't dial out.. it's some sort of floating pivot, which i can see would cause some shizzy mush.. but it's there for a reason, i suspect, although i dunno WHY you would introduce that sorta motion in a brakeset.
Hmmm, there's one culprit. There shouldn't be any play in the QR mechanism. I would take that apart and inspect. Might be as simple as a missing washer. I'm not familiar with that brake and don't know if they're similar to the Shimano brakes where you can turn the QR to any position to adjust the caliper open-position. Or if the DC brakes are either all open or all closed but nothing in between.
DannoXYZ is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Raleigh74
Classic & Vintage
28
02-14-19 05:23 PM
AZORCH
Classic & Vintage
5
08-02-17 05:37 PM
uRabbit
Bicycle Mechanics
13
03-27-17 04:38 PM
apg
Bicycle Mechanics
11
05-02-15 06:55 AM
jameskb101
Classic & Vintage
15
02-01-14 09:27 PM

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.