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Speedbiker
human power expert

USA
3835 Posts

Posted - 02/26/2014 :  07:51:58  Show Profile  Reply with Quote
I'm sure it will come out as nice as your other terrific builds.
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mhelander
recumbent enthusiast

Finland
384 Posts

Posted - 03/06/2014 :  04:58:28  Show Profile  Reply with Quote
Thanks Thom.

I've purchased 44mm headset tubing, BB shells, rear dropouts and disc caliber tabs... here we go. I've also found and contacted Finnish dealer for Aircraft Spruce CrMo tubing.

Cheers,
-Mika

Diy bents: Full-suspended off-roader @ 2012, Vendetta clone @ 2012
Commerials: MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
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mhelander
recumbent enthusiast

Finland
384 Posts

Posted - 08/27/2014 :  06:12:49  Show Profile  Reply with Quote
quote:
Originally posted by Speedbiker

I'm sure it will come out as nice as your other terrific builds.



Aha. Not much happened but during the year I've acquired parts to replace some current ones and right now I've got enough stuff sans rear shifter and crankset to build next prototype.

Since last updated I've got excited about middle-drive as rear swingarm pivot and chopping disc hub pairs to merge disc flanges so that left side both in hub and middle-drive hosts 6-bolt cog(s) and brake disc is in right side with floating caliper mount flange.

I've ridden way over 4000 km's year to date this without any issues with RD and thus middle-drive idea is buried. Constructing frame for seat support, middle-drive pivoting and rear suspension is complicated as such and likely not worth the effort.

Before putting full steam on in building I've been experimenting ideas to target simplified construction and ease up riding. Latest is to try 1x9 gearing with single 10% oval 34t chainring and custom 9sp cassette built from two SRAM PG970 cassettes, 11-32 and 11-34, and Hope T-Rex 40t cog:





This setup has now gears as 11-13-15-18-21-24-28-34-40 and SRAM X.9 Type2 10sp RD modified for 9sp wire pull. Here is how gearing is spread:



Rode bent through easy rock garden and sunking swamp this morning. Gearing works and is easy to use. Shifting is little weaker between cogs from different cassettes but fortunately three smallest gears (=biggest cogs) shift very well.

Worth noting is that short-cage Type2 RD is likely met its chain management limits. After adding one link pair to chain and fiddling with B-tension bolt got it dialed in well enough. I was surprised that Type2 cage has limited rotation which almost broke RD and bent its hanger while testing 40t without added links.

Seems I'm dropping FD, cabling and shifter from new build. And as my current oval chainrings have seen over 10,000 km's riding it's time to try to make narrow-wide 10% oval 34t chainring. Likely overkill but I need little stronger ring and MTB folks are mostly reporting that no chain dropping with properly shaped narrow-wide rings. Rotor QX1 and their very nice Rex 1.1 crankset are just too much quality and cost.

Cheers,
-Mika

Diy bents: Full-suspended off-roader @ 2012, Vendetta clone @ 2012
Commerials: MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
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alevand
human power expert

USA
3476 Posts

Posted - 08/27/2014 :  09:05:10  Show Profile  Visit alevand's Homepage  Reply with Quote
It would be nice to have some overlap between chain rings, other wise you have to double shift through the whole cassette.

C:
Tony Levand

Edited by - alevand on 08/27/2014 09:07:03
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mhelander
recumbent enthusiast

Finland
384 Posts

Posted - 08/27/2014 :  09:27:59  Show Profile  Reply with Quote
Sure. But that's not problem with single narrow-wide chainring... Which is my target.

Currently having triple crankset with 25t/34t 10% ovals and round 46t which is newer used. This summer used 25t only few times.

Cheers,
-Mika

Diy bents: Full-suspended off-roader @ 2012, Vendetta clone @ 2012
Commerials: MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
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mhelander
recumbent enthusiast

Finland
384 Posts

Posted - 09/30/2014 :  01:07:40  Show Profile  Reply with Quote
Since getting in speed with this superb 1x9 wide range more updates to follow, saw big discount in Hope Race Evo X2 hydraulic disc brake, british rear left-hand. Perfect to be used as recumbent front brake... selected Hope Tech3 X2 rear right-hand to pair and this is how it looks:



Cockpit view... very little obstacles now as levers are skinny but still modulation is exceptional. Appreciate little heavier Tech3 rear lever and its quick adjusters.



Rear caliper, very nice, skinny and pads are swapped without removing wheels.

As this is now 1x9, dropping FD & trigger & cabling, and swapping Hayes HFX-9 brakes to Hope, 575 grams were skimmed off. Not bad but tad expensive tho.

Then made good purchase of used Rock Shox Reba Team 115mm dual-air fork. Little less travel than older Fox Vanilla R 130mm but air instead of coil spring was to provide better tuning.

Fork shoulders are really slim so had to do remote steerer tab from 8mm 7xxx series aluminium:



First ride with this setup was exceptional. Fork works without any accent but steering is very much more accurate and sensitive. Coil spring fork apparently had little non-suspended bouncing in short travel and wear in lower leg bushings... remote steerer tab was slipping some thus had to do quick fix to regain confidence to steering.

Next was time to build new wheelset using already received chinese all-carbon wide hookless rims. Front is 27mm ID 33mm OD and rear 30/35mm. That's way wider than WTB LaserDisc rims with ID's 19mm front and 21mm rear. Target was to get stiffer and wider rims to stabilize more use of MTB slick tires setup for tubeless and low pressures, and lessen burping which sometimes happens with WTB rims.

Used same WTB LaserDisc Lite disc hubs and DT-Swiss Revolution 2.0/1.5 double-butted spokes with brass nipples, weight was shaved off along the way from 1854 grams to ~1554 grams per wheelset, not bad 300 grams savings and all from rotating mass. Installed Hope 160mm brake discs and moved Schwalbe Thunder Burt 54mm tubeless tires setup to this wheelset, tires are now 2-3 mm wider and first rides and races confirmed super stable ride and very fast cornering in gravel, still good rolling in any surfaces.

As all was working so well in 1x9, it was time to execute long dreaming to upgrade crankset. I've had to date crankset from my -94 MTB, upgraded with DIY 10% oval 25t/34t chainrings and FSA UlTiMax titanium square taper BB. Plan was to get road length crankarms, 172.5mm, and commercial oval single chainring, preferably narrow-wide type. After long search there was only two cranksets meeting all criterias, some Shimano CX model and Rotor REX cranksets. And at times Rotor was only to have narrow-wide oval chainring... Found reasonable deal for REX 2.1, QX1 34t oval chainring and BSA30 bearing set which is now installed:





As stock non-even mounting of QX1 ring wasn't good for RWD recumbent had some fun making tool from GXP BB bearing cup socket and then dialing REX spider so that ring is about same 5 degree advanced as I'm used to with my other oval setups. First ride to test Rotor crankset was transfer to cyclo-cross event where found out that my torque was better than before with 10% oval rings in 170mm crankset. Weight was skimmed down from 968 grams to 698 grams which includes all included shims, some not needed in BSA30 install. Another nice 270 grams less and again tad expensive.

Here are not so great pictures of the wheelsets:



Front rim is actually deeper and both are more aero than typical MTB rims, good for my faster speeds in flats. Hope brakes are really good after disc & pads break-in, modulation is so good that now with more accurate steering riding is more relaxed and faster than before.

Total weight of the bent in racing fit was about 18.1 kg quickly scaled. This is about as light it goes with sensible investment before building better, stiffer and lighter frame from CrMo...

Cheers,
-Mika

Diy bents: Full-suspended off-roader @ 2012, Vendetta clone @ 2012
Commerials: MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010

Edited by - mhelander on 09/30/2014 02:47:09
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mhelander
recumbent enthusiast

Finland
384 Posts

Posted - 09/30/2014 :  01:16:23  Show Profile  Reply with Quote
Unfortunately broke remote steering clamp last Sunday when rode to last race of three in XC Cup. Fortunately no serious issues in race but while doing extended transfer to meet my weekly metric century leg target went down while passing a ditch and then found out that clamp bolt ripped threads away.

After pushing bent to nearby gravel sports track got it fixed using racing number plate's zip-tie well enough to complete rest 30 km's of that ride. Time to tinker or do another tab...

As fork shoulders are too slim for drill & thread mount, and having slim enough steerer tab to hold lower race of headset, one idea might be to merge clamp tab and this:



Plan is to do non-clamping tabs to both fork's left lower stanchion and steerer. Use M8 bolt or rod with nylock nuts to bolt those together, and mount remote steerer pivot as high as possible but as near 90 degree in relation to steerer.

Let's see can I do it today for tomorrow's CX event or use Fox fork instead.

Cheers,
-Mika

Diy bents: Full-suspended off-roader @ 2012, Vendetta clone @ 2012
Commerials: MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
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