Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Folding Bikes Discuss the unique features and issues of folding bikes. Also a great place to learn what folding bike will work best for your needs.

Reply
 
Thread Tools Search this Thread
Old 03-17-14, 06:38 PM   #1
keyven
Senior Member
Thread Starter
 
Join Date: Oct 2013
Location: Singapore
Bikes: Giant Anthem X1 2009; Brompton M2R 2014; Brompton Ti M6R 2014
Posts: 1,087
M6R - 76mm skate wheels on one side, 78mm on other?

After installing 76mm wheels, the bike seems to favor the handle side when rolling along folded. It tilts somewhat too easily due to the handlebar, so I'm thinking of switching the handlebar's side wheels to 78mm to tilt it slightly back towards the non-handlebar side and keep it more balanced overall.

76 76
== ==
======----//
======----\\
== ==
78 78mm
-Handlebar drops on this side, so the 2mm difference could make the folded bike favor the non-handle side a little more.

Would that make any sense?

Last edited by keyven; 03-17-14 at 11:28 PM.
keyven is offline   Reply With Quote
Old 03-17-14, 08:25 PM   #2
cplager 
The Recumbent Quant
 
cplager's Avatar
 
Join Date: Jan 2012
Location: Norwalk, CT
Bikes: 2012 Cruzbike Sofrider, 2013 Cruzigami Mantis
Posts: 3,017
Huh.

Not completely crazy. Try it and take pictures.
cplager is offline   Reply With Quote
Old 03-18-14, 12:49 AM   #3
keyven
Senior Member
Thread Starter
 
Join Date: Oct 2013
Location: Singapore
Bikes: Giant Anthem X1 2009; Brompton M2R 2014; Brompton Ti M6R 2014
Posts: 1,087
Quote:
Originally Posted by cplager View Post
Huh.

Not completely crazy. Try it and take pictures.
A bit tough to find 78mm wheels in Singapore... no one carries them anymore so I have to pick them up from Amazon... sigh.
keyven is offline   Reply With Quote
Old 03-18-14, 08:51 AM   #4
fietsbob 
coprolite
 
fietsbob's Avatar
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Bikes: 7
Posts: 18,087
1mm difference in radius doesn't seem significant..
If 76&78 are both diameters. given r=1/2D

NB: only the bottom half will affect the tilt, and that by definition is radius ..

Last edited by fietsbob; 03-19-14 at 10:03 AM.
fietsbob is offline   Reply With Quote
Old 03-19-14, 10:00 AM   #5
keyven
Senior Member
Thread Starter
 
Join Date: Oct 2013
Location: Singapore
Bikes: Giant Anthem X1 2009; Brompton M2R 2014; Brompton Ti M6R 2014
Posts: 1,087
Quote:
Originally Posted by fietsbob View Post
1mm difference in radius doesn't seem significant..
If 76&78 are both diameters. given r=1/2D
The total difference (diameter) is 2mm, which hopefully will be sufficient to correct the minor tilt. I worry 80mm is overkill.
keyven is offline   Reply With Quote
Old 03-19-14, 10:13 AM   #6
BruceMetras
Senior Member
 
Join Date: Aug 2005
Location: San Rafael, California
Bikes:
Posts: 1,846
Quote:
Originally Posted by keyven View Post
The total difference (diameter) is 2mm, which hopefully will be sufficient to correct the minor tilt. I worry 80mm is overkill.
If you are trying to raise one side, the 1mm difference above the centerline doesn't count.. only the 1mm below .. 76mm/2 =38mm 78mm/2=39mm 80mm/2 =40mm .. so if you want to raise one side 2mm, then 80mm is what you want to use to go with 76mm .. I'd start thinking heel strike though..
BruceMetras is offline   Reply With Quote
Old 03-19-14, 10:17 AM   #7
fietsbob 
coprolite
 
fietsbob's Avatar
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Bikes: 7
Posts: 18,087
the EZ wheel is bigger than the standard roller
perhaps leave the standard rollers front and rear on the left side

Bromfication custom machines a roller that is thinner so less heel strike is a second gain..
& they are pretty .. anodized Aluminum with a thinner O ring 'tire'
fietsbob is offline   Reply With Quote
Old 03-19-14, 10:21 AM   #8
keyven
Senior Member
Thread Starter
 
Join Date: Oct 2013
Location: Singapore
Bikes: Giant Anthem X1 2009; Brompton M2R 2014; Brompton Ti M6R 2014
Posts: 1,087
Quote:
Originally Posted by BruceMetras View Post
If you are trying to raise one side, the 1mm difference above the centerline doesn't count.. only the 1mm below .. 76mm/2 =38mm 78mm/2=39mm 80mm/2 =40mm .. so if you want to raise one side 2mm, then 80mm is what you want to use to go with 76mm .. I'd start thinking heel strike though..
Yeah heelstrike is definitely a problem even with 76mm wheels so I'm not quite prepared to try any bigger than I need to.
keyven is offline   Reply With Quote
Old 03-19-14, 10:24 AM   #9
keyven
Senior Member
Thread Starter
 
Join Date: Oct 2013
Location: Singapore
Bikes: Giant Anthem X1 2009; Brompton M2R 2014; Brompton Ti M6R 2014
Posts: 1,087
Quote:
Originally Posted by fietsbob View Post
the EZ wheel is bigger than the standard roller
perhaps leave the standard rollers front and rear on the left side

Bromfication custom machines a roller that is thinner so less heel strike is a second gain..
& they are pretty .. anodized Aluminum with a thinner O ring 'tire'
Hmm that sounds interesting... maybe I'll look up their site.
keyven is offline   Reply With Quote
Old 03-19-14, 02:17 PM   #10
bhkyte
Senior Member
 
bhkyte's Avatar
 
Join Date: Sep 2008
Location: York UK
Bikes: 2X dualdrive Mezzo folder,plus others
Posts: 2,773
Its not the size of the wheel To avoid heel strike afaik . Of you use a rollerblade wheel just use the outside bearing and glue the wheel to the bearing. I think 2 mm makes sense from memory to keep stable without going around in circles.
bhkyte is offline   Reply With Quote
Old 03-19-14, 07:59 PM   #11
keyven
Senior Member
Thread Starter
 
Join Date: Oct 2013
Location: Singapore
Bikes: Giant Anthem X1 2009; Brompton M2R 2014; Brompton Ti M6R 2014
Posts: 1,087
Quote:
Originally Posted by bhkyte View Post
Its not the size of the wheel To avoid heel strike afaik . Of you use a rollerblade wheel just use the outside bearing and glue the wheel to the bearing. I think 2 mm makes sense from memory to keep stable without going around in circles.
That's good to hear. Thanks.
keyven is offline   Reply With Quote
Old 04-08-14, 09:52 PM   #12
keyven
Senior Member
Thread Starter
 
Join Date: Oct 2013
Location: Singapore
Bikes: Giant Anthem X1 2009; Brompton M2R 2014; Brompton Ti M6R 2014
Posts: 1,087


Well, I've been using it for more than 2 weeks and it's everything I hoped for.

Fantastic stability regardless of whether I'm pushing or pulling it. I can run with it on most flat surfaces without feeling like it's going to tip over suddenly.

It actually pushes in a straight line noticeably better than when it was 76mm for all four sides.
Attached Images
File Type: jpg 20140404_202310.jpg (88.1 KB, 58 views)

Last edited by keyven; 04-08-14 at 10:35 PM.
keyven is offline   Reply With Quote
Old 04-09-14, 06:54 AM   #13
cplager 
The Recumbent Quant
 
cplager's Avatar
 
Join Date: Jan 2012
Location: Norwalk, CT
Bikes: 2012 Cruzbike Sofrider, 2013 Cruzigami Mantis
Posts: 3,017
Quote:
Originally Posted by keyven View Post

Well, I've been using it for more than 2 weeks and it's everything I hoped for.

Fantastic stability regardless of whether I'm pushing or pulling it. I can run with it on most flat surfaces without feeling like it's going to tip over suddenly.

It actually pushes in a straight line noticeably better than when it was 76mm for all four sides.
Nice!

Thanks for the update.
cplager is offline   Reply With Quote
Old 04-09-14, 07:29 AM   #14
keyven
Senior Member
Thread Starter
 
Join Date: Oct 2013
Location: Singapore
Bikes: Giant Anthem X1 2009; Brompton M2R 2014; Brompton Ti M6R 2014
Posts: 1,087
Np, I'd highly recommend it and may even try 72-76 4mm difference in the near future since I have the wheels on hand.
keyven is offline   Reply With Quote
Old 04-09-14, 11:23 AM   #15
fietsbob 
coprolite
 
fietsbob's Avatar
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Bikes: 7
Posts: 18,087
Quote:
Yeah heelstrike is definitely a problem even with 76mm wheels so I'm not quite prepared to try any bigger than I need to.
the issue is width- wheel thickness , not diameter .. Brompton's EZ wheel is 10mm thick 60 in diameter.. width 140 mm overall.

the bromfication ones are stated as 51mm Dia and thinner (not here to measure)

Last edited by fietsbob; 04-09-14 at 11:28 AM.
fietsbob is offline   Reply With Quote
Old 04-10-14, 05:51 AM   #16
bhkyte
Senior Member
 
bhkyte's Avatar
 
Join Date: Sep 2008
Location: York UK
Bikes: 2X dualdrive Mezzo folder,plus others
Posts: 2,773
Re 78 mm hockey wheels.

you need to skate around in a set on 80mm untill they become 78mm!!
A good skater can reduce them in about 2 mins doing hockey stops and turns.
I can shred them in about 10 mins to the core.
bhkyte is offline   Reply With Quote
Old 04-10-14, 09:20 PM   #17
keyven
Senior Member
Thread Starter
 
Join Date: Oct 2013
Location: Singapore
Bikes: Giant Anthem X1 2009; Brompton M2R 2014; Brompton Ti M6R 2014
Posts: 1,087
Quote:
Originally Posted by bhkyte View Post
Re 78 mm hockey wheels.

you need to skate around in a set on 80mm untill they become 78mm!!
A good skater can reduce them in about 2 mins doing hockey stops and turns.
I can shred them in about 10 mins to the core.
I can only hockey stop perfectly on one side. The other still feels somewhat unnatural. As such, most of my wheels become very lop-sided and I don't bother to change them until it's too late. I find T-stops are better for 'burning off' the rubber though.

Kinda feel the 76/78mm are still too prone to heelstrike and now I'm aiming to get as small as possible. The extreme low end would be 62/64, but 64mm is very hard to find in Singapore. I may have to settle for 68/70mm which are far more common.
keyven is offline   Reply With Quote
Old 04-10-14, 09:36 PM   #18
keyven
Senior Member
Thread Starter
 
Join Date: Oct 2013
Location: Singapore
Bikes: Giant Anthem X1 2009; Brompton M2R 2014; Brompton Ti M6R 2014
Posts: 1,087
Quote:
Originally Posted by fietsbob View Post
the issue is width- wheel thickness , not diameter .. Brompton's EZ wheel is 10mm thick 60 in diameter.. width 140 mm overall.

the bromfication ones are stated as 51mm Dia and thinner (not here to measure)
Well, that is true but unfortunately that would mean the only choice would be the Bromification ones since I'm never going back to Eazy wheels.

Wheel thickness definitely plays a part in heelstrike, though not as much as diameter. A thinner, slightly smaller wheel just means I can shimmy my feet a little more onto the pedal while reducing the chance of heelstrike as well.
keyven is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

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



All times are GMT -6. The time now is 07:23 AM.