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Full suspension FWD MBB - some advice needed.

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Balor View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Balor Quote  Post ReplyReply Direct Link To This Post Posted: 09 March 2018 at 10:16am
Originally posted by GeoffBird GeoffBird wrote:

I'll have to see the bike in the link when it is finished. Please Private Message me your email and I'll send you some stuff about my bike.

Nothing all that interesting, really, just a variation on a theme of a Zimin's latter bikes:

https://www.vershina.info/

His first MBBs were extremely unorthodox and likely work very well for what they were intended to accomplish (MBB with VERY little flop, pedal feedback and steering inertia due to BB located ON the steering axis), but it involves sacrifices I'm not willing to make :).

https://www.vershina.info/moi-velosipedy

As for rear swingarm, it is akin to Toxy ZR:
http://www.toxy.de/index.php/en/products/toxy-zr

Unfortunately, it might be scrapped in favor of conventional swingarm (or even no suspension at all) because the builder has little access to good tooling and improvisation only gets you so far.
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Balor View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Balor Quote  Post ReplyReply Direct Link To This Post Posted: 13 March 2018 at 9:33am
After some ruminations, I think I'll be doing it 'as pictured' anyway.
It WILL bob, I'll just go with much less (or, indeed, zero) sag for smoother roads (of course it would result less useable travel, but this is better than nothing) and for really rough roads some bob is 'lesser evil'. Air shock allow for easy tuning.
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Balor View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Balor Quote  Post ReplyReply Direct Link To This Post Posted: 08 June 2018 at 3:53pm
The project is nearing completition:
 
 
 
 
Builder reports that suspension works very well and does not seem to bob much.
It would be a while before I'll be able to test ride it myself, so I'll have to be content with reports like that so far :)


Edited by Balor - 08 June 2018 at 3:58pm
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Balor View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Balor Quote  Post ReplyReply Direct Link To This Post Posted: 08 June 2018 at 4:13pm
By the way, there is a funny thing about FWD 'reverse bob' and climbing steep inclines.
 
As you climb steep stuff, you front end is unweighted, hence if you run little sag - you get zero sag and, therefore, zero bob exactly when you need it most :)! Kind of 'intelligent lockout', only 100% passive.
 
Cannot have that on RWD, ehehe. Talking about 'turning a liability into an advantage'.


Edited by Balor - 08 June 2018 at 4:15pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Balor Quote  Post ReplyReply Direct Link To This Post Posted: 29 June 2018 at 10:11pm
Maiden voyage!
https://www.strava.com/activities/1670046779

[IMG] 

I daresay it is fast enough for a FS bent with body position (low BB) and crank length I'm not familiar with yet.
"Cruzbike cockpit' with 'seagull bars' is great and short cranks allow for comfortable arms position without my knees hitting anything in the process.
I should note that road on that track is very bad, with lots of potholes and rough, weathered asphalt.  Funny enough, front suspension seems much 'smoother' than the rear - likely due to heavy front weight bias (hence much larger suspended mass) and rearward axle path.
Among 3 MBB bents I've tested (Zorkra Clone, MBB with negative angle and this one) - this is the most easily steered bike, despite front triangle weighting a ton. One-handed operation is trivial, riding no-hands is ALMOST doable even for an oaf like me! I bet I'll get the hang of it eventually.
Basically, ride has a 'relaxing' quality that my previous MBB bents sorely lacked. You don't feel like being from one small hand twitch from lying in a ditch :) Yet, you can 'swing the boom' for power and pull the bars and stomp the pedals and get rewarded with feel of power NOT being lost anywhere.
I should note that suspension does NOT bob at all at least when cruising on flat ground - something that came as a surprise for me, actually.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Yanto Quote  Post ReplyReply Direct Link To This Post Posted: 30 June 2018 at 9:27pm
Just to prove that somebody is reading your posts, I think it's brilliant, and don't take this the wrong way but built in a style that Russian military equipment has: robust, fit for purpose and no frills Big smile
Ian, retired.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Balor Quote  Post ReplyReply Direct Link To This Post Posted: 03 July 2018 at 9:14am
Thanks! I don't mind frills so long as they serve a practical purpose :).
As an update, I've nearly beaten my previous 'course record' - of 36 km/h over 16 km (loop track with turnabout).
After installing longer shock in the rear, the steering angle is exactly 90 deg (maybe 90.2 or something) and it is very easy to wheel around now, no flop at all.
I've finally managed riding (coasting so far) no-hands - which is actually a huge achievement for be, because previously on MBB bents I've had trouble even riding one-handed (sipping from a water bottle was invariably scary).
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Yanto Quote  Post ReplyReply Direct Link To This Post Posted: 04 July 2018 at 9:01pm
One of the reasons i prefer 3 wheels is the ease of faffing with drinks bottles, snacks and stuff without a trip into the shrubs, looks like you've got that aspect sorted.
Ian, retired.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Balor Quote  Post ReplyReply Direct Link To This Post Posted: 05 July 2018 at 3:01pm
Not *yet* truth be told, coasting is doable but not pedalling. But it took me a long time to do no-hands even on DF bike, so guess I'll get there eventually.
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