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 Fully suspended off-road bent

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T O P I C    R E V I E W
mhelander Posted - 11/19/2012 : 15:05:11
Some may remember that I did try off-roading, riding MetaPhysic dual 700c converted to MetaPhrastic 29er (full-carbon disc fork, 33mm knoppy tires, less reclined seat, SPD pedals):



That didn't went too well, front of bike was bouncing everywhere when trying to keep speed on roots, rocks or sharp bumps. And my back didn't like inadequate cushion of Ventisit so called that 6h race quit after little over 4 hours.

Since completed FWD-MBB Vendetta clone successfully it was time to start planning what kind of off-road bent would be better. About spring time noticed Craig's off-roader built by Rob English:



This looks promising, big wheels, longer wheelbase, no heel clearance issues. But USS... not my thing. Maybe something like this:



Remote steering, to avoid waving arms while steering which has impact to balance.

Craig's and Rob's rear suspension looks very interesting:




I like that. Keeps rear shock in nice place, and as Craig later told me it's designed to have different progression than typical designs.

Planned to get somewhere aluminium donors for little lighter frame, but instead got two cheap "walmart" kind of bikes and one little better quality one. Time to have plenty of cutting discs to angle grinder and start working:



Here most of main frame is put together, compared to MP in winter trim. Next rear fork:






And almost ready frame in its own wheels:



Next to make pivoting system for rear suspension and position it after fork pivot and add last missing piece of frame. But before it did finish remote steering while waiting rear shock's shipping:




Drilled hole to best possible place in fork shoulder, then tapped it and using blue Loctite put piece of stainless threaded stud. Remote end has chopped fork where welded stud for joint.

Then rear pivoting system. Don't have access to milling machines to fabricated pieces from 3mm aluminium plate, suitable ID tubing and welded those together:




I'm using ABEC 7 inline roller skate bearings as had those available and local bearing shop didn't have anything better to offer.

Then did arm from fork to triangle and started fitting rear suspension details together.




Seat fits well above shock, that's Rock Shocks 190mm one with 50mm travel. That tube behind triangle is donor frame's seat tube, decided to do removable and adjustable upper mount support for seat:




Here is shock front mount and seat mount ready:




After completing rear suspension mechanisms measured its travel and it's about 170mm or little more. Fork is 130mm.

And it's ready for virgin test-ride:



This rides very well. I can even pedal no hands ! Steering is good and turning radius about good enough for my kind of use. Suspension is very good, no pogo, while pedaling no "kick" to pedals when suspension does its job. This can keep serious speed in rough terrain.

It's little heavy, suitcase scale stopped to 19.95 kg. It could loose weight about 1 kg as I have very heavy Quando wheelhubs and could use couple of lighter components like threaded stud in remote steering and tiller setup. Maybe I'll keep engine's fat % in control instead.

Didn't use hydraulic disc brake @ rear, did put it to front as tubing was just about long enough there. And availability of Hayes compatible tubing & fittings is not so good... decided to order BB7 road brakeset for MP and took its MTB one here.

No much invested, needed extra sturdy threadless headset, rims, tires and rear shock as new. Also got SRAM 7sp cassette to fit modern disc hub and so able to use 3x7 $himano RD's and original Grip Shift's from -90's MTB. Bought fork and hydraulic disc brakes used.

Now I have two bents for winter season: MP with friction tires when having harder snowy or icy conditions, and this off-roader for wet or more snowy courses.

Target is to iron out bugs before next spring's 6h off-road race.

Cheers,
-Mika

Diy bents: Full-suspended off-roader @ 2012, Vendetta clone @ 2012
Commerials: MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
25   L A T E S T    R E P L I E S    (Newest First)
mhelander Posted - 09/30/2014 : 01:16:23
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
mhelander Posted - 09/30/2014 : 01:07:40
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
mhelander Posted - 08/27/2014 : 09:27:59
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
alevand Posted - 08/27/2014 : 09:05:10
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
mhelander Posted - 08/27/2014 : 06:12:49
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
mhelander Posted - 03/06/2014 : 04:58:28
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
Speedbiker Posted - 02/26/2014 : 07:51:58
I'm sure it will come out as nice as your other terrific builds.
mhelander Posted - 02/26/2014 : 04:05:53
Tinkering about building next revision of this bent has been ongoing for ages... I've got far enough than planning on mail-ordering quality CrMo tubing for building two new framesets, large and small sizes, to be used by me and my daughter.

Main frame beam will likely be 1-3/4" round in 0.049" wall. Rear fork from 1-1/4" and 0.049". Remote steerer for 1-1/8" threadless headset and 1-1/8" 0.049" CrMo stem.

Then proper CrMo BB lug, hopefully tapered 1-1/8" to 1.5" suspension fork steerer and nice disc & RD dropouts from somewhere.

Hollow tube through industrial sealed bearings for rear swingarm, tube preload and clamping still open. Shock linkage triangles with two frame mounting position with bearings in frame side.

New idea is to plan frame geometry so that remote steerer can be used for rigid 29er or road (carbon) fork with tiller setup, and seat more reclined. Much like my MetaPhysic, to be used for road and touring riding. TroyTec kind of "full suspension" via middle frame pivoted rear suspension and about 60mm travel. Or with 100+ mm suspension fork and remote steering for real off-road use.

Upper rear shock mount, power idler and 2-4" adjustable seat mounting is still open. Likely will require stiffened composite seat as now but seat mount will have fixed power idler mount and is adjusted in relation to BB together.

Next to do little bit of drawing and dimensioning, ordering stuff etc...

Cheers,
-Mika

Diy bents: Full-suspended off-roader @ 2012, Vendetta clone @ 2012
Commerials: MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
mhelander Posted - 11/18/2013 : 06:41:53
I've got pretty excited about thread Advice wishbone A-arm + leaf front suspension and use of composite leaf string for suspendind and damping...

Spent some time figuring out rationale behind Corvette's leaf suspension and use of such leaf in this off-road bent. It seems this might work and could really simplify rear suspension details.

Here is my rear swingarm:



And its position in main frame:



Now think about putting single flat composite leaf below frame tube, front mount just behind remote steerer and rear mount under swingarm H-tube. Then adjustable middle holder between leaf and frame tube.

That would be very simple, stiffness at least partially adjustable and maybe some damping could be introduced by placing rubber dampers between frame mounts. Total movement of the swingarm's H-tube is about 5-7 cm which composite leaf is to handle.

Also placing leaf below frame tubing would simplify seat mount altogether and maybe seat could be placed little lower too. At least constructing adjustable seat mounts would be much simpler with this.

This pegs building another steel prototype frame and composite leaf from cheap epoxy and twill glass fiber...

Cheers,
-Mika

Diy bents: Full-suspended off-roader @ 2012, Vendetta clone @ 2012
Commerials: MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
mhelander Posted - 11/18/2013 : 03:27:36
quote:
Originally posted by mhelander

I've put Ice Spiker Pro tires on my wheelset which had Furious Fred slicks. Those are just too unpredictable to ride on muddy gravel roads and wet grass. Let's see how well those roll when setup as tubeless. 361 spikes @ front and 402 @ rear almost require use of ear plugs when on tarmac.


Yes, ISP's work quite well even in single-track. But those are slipping like crazy on snow-less rocky terrain and in one (52 km) leg I lost 5 studs from front and 40 (!) from rear tires.

So my other wheelset got Conti TopContact II Winter friction tires, 50-557 front and 37-622 rear. Working somehow in fine gravel and off-road, still rolling worse than Furious Freds in tarmac.

I'm waiting snow to stay on ground...

quote:
Originally posted by mhelander



Above is this new applauded Type2 RD with jockey cage clutch. As 10sp RD's have smaller wire guide I'm going to shape hard foam for proper dimensions and when proven functional wrap it over using epoxy+carbon, and mount using zip-ties.

If successful, I have very rare SRAM-only clutch RD in my 9sp system. Likely beneficial with so long chainline, DH level rear suspension which with non-clutch RD has removed most of the paint from rear swingarm.


Here we go:





Made that piece from epoxy slab hardened in cup. Attached to original cable guide using hot glue and steel wire, zip-tie keeps cable in new guide groove.

That bottom part did drop early so now I have another cup of hardened epoxy, mixed with splitted scrap carbon strings so it'll be tougher than this one.

Here is this bent in its current form, taken when had my 1st leg on snow this fall:



This leg was to test modified RD and it worked very well. Almost no chain slapping at all when pedaling over very rough terrain. No chain drops. Shifting both front and rear same time is little affected.

Equipped with WTB Bronson Race knobby tires good for snow and wet conditions, but impossibly slippery on wet hard snow or ice. Went down once in 30 kph speeds that day...

That leg initiated breakage of my homebuilt seat. It's my fault, I've done flimsy upper seat support to just keep seat in its place, relying on seat ribs and their rigidity. First other rib fractured, then later other also fractured which dropped seat some 2-3in and put seat to almost as reclined as in my road bents.





Had only one carbon cloth and carbon+nomex cloth in ribs, that wasn't enough to resist my merciless offroad riding and forces put to it by my upper torso. Didn't help that seat is mounted well from front of bottom pan, like in M5 lowracer, and supported well from lumbar curve area. Big bending forces to opposite direction than seat's been designed for.

Now fractures are repaired using patch of dual-uni cloth, then another carbon and carbon+nomex cloths over longer area of the ribs to make seat sturdy enough to work with that flimsy upper support. Used peel ply with absorbing cloths and proper compression, way better than when built that seat originally.

Didn't add much to seat weight (sub 100g), way less than building stronger support for it.

First test rides proved that seat's more solid than ever before. Especially when comparing its rigidity to MetaPhysic's seat I used while fixing this.

Cheers,
-Mika

Diy bents: Full-suspended off-roader @ 2012, Vendetta clone @ 2012
Commerials: MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
mhelander Posted - 10/08/2013 : 13:27:57
quote:
Originally posted by Speedbiker

Amazing work, Mika.



You mean my zip-tie magic? It was just few minutes to figuring out how and where route those so that RD moves as expected.

Modifying Type2 isn't done yet.

Cheers,
-Mika

Diy bents: Full-suspended off-roader @ 2012, Vendetta clone @ 2012
Commerials: MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
Speedbiker Posted - 10/08/2013 : 06:57:20
Amazing work, Mika.
mhelander Posted - 10/08/2013 : 06:32:59
I've put Ice Spiker Pro tires on my wheelset which had Furious Fred slicks. Those are just too unpredictable to ride on muddy gravel roads and wet grass. Let's see how well those roll when setup as tubeless. 361 spikes @ front and 402 @ rear almost require use of ear plugs when on tarmac.

I've also broken my X.7 RD in final Wednesday cyclo-cross race. After very successful start, from position 8-9, chain jumped between cog and spokes. When getting chain back to cog noticed that RD jockey wheel was against cogs so B-bolt limiter tab was obviously broken away.

I've got my RD between spokes couple of weeks ago and used brute force to get it back and bent hanger properly to make rest of that leg. Apparently B-bolt tab got fracture then and it unfortunately gave up in the race.

As I absolutely hate to DNF from races, coasted back to starting area and used plenty of zip-ties to get RD back to intended position, and finished the race losing about three laps while fixing.



And broken part is that shim's bottom tab:



(sorry for blurry pictures, better ones are here and here)

Fortunately I have X.9 10sp RD in lowracer so stole broken shim to fix X.7 while waiting new RD which will be X.9 Type2. As those are only available for 10sp systems and mine is 9sp, I'll try to add radius to wire guide for matching 9sp wire pull ratio.

I've got my inspiration from daVinchi Design (see heading "Custom Rear Derailleur") :



RD above is modified for different trigger shifter and below is unmodified 9sp, both X.9 new design RD's. daVinchi uses quite rough method where rivets holding wire guide are drilled out and new guide is mounted using bolts and nut.



Above is this new applauded Type2 RD with jockey cage clutch. As 10sp RD's have smaller wire guide I'm going to shape hard foam for proper dimensions and when proven functional wrap it over using epoxy+carbon, and mount using zip-ties.

If successful, I have very rare SRAM-only clutch RD in my 9sp system. Likely beneficial with so long chainline, DH level rear suspension which with non-clutch RD has removed most of the paint from rear swingarm.

Cheers,
-Mika

Diy bents: Full-suspended off-roader @ 2012, Vendetta clone @ 2012
Commerials: MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
Speedbiker Posted - 09/23/2013 : 07:59:19
Notice how despite living in a cold climate, with multiple bikes Mika's kilometers really add up. Instead of ordering spiked tires I am organizing my indoor trainer area. And this is Ohio, not Finland!
mhelander Posted - 09/23/2013 : 02:06:08
Nice LWB Duram.

My offroader is ridden now over 4400 km according to Strava where I started to enter my rides since Jan 2012. That's more than I've ridden lowracer (just under 4400 km), MetaPhysic (just under 4000 km) and diy-Vendetta (just under 2000 km).

I've said to anyone asking that if I can keep only one bent it'll be this for sure.

Cheers,
-Mika

Diy bents: Full-suspended off-roader @ 2012, Vendetta clone @ 2012
Commerials: MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
duram Posted - 09/07/2013 : 19:13:18
This one is ready for all off-road and is fully suspended, 26 x 26
LWB called Truck D4.

Carry up to 30 Kgr and until now has 6200km ridden, very nice
bike made by Zohrer, now is not produced anymore.

www.zohrer.com.br



mhelander Posted - 08/15/2013 : 14:20:38
quote:
Originally posted by Speedbiker

Winter comes early in Finland. Mika is ready.



Yes, I'm ready... Ice Spiker Pro tires are waiting...

But hopefully we have some summer time riding weathers left for couple of racing events. It's getting colder and rainier but no biggie, yet.

Cheers,
-Mika

Diy bents: Full-suspended off-roader @ 2012, Vendetta clone @ 2012
Commerials: MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
Speedbiker Posted - 08/15/2013 : 13:59:05
Winter comes early in Finland. Mika is ready.
mhelander Posted - 08/14/2013 : 23:45:34
Little update for this bent.

Did some tire testing procedures, to see are Schwalbe Furious Fred 50-559 & -622 tires better for me and courses I've raced than Racing Ralph Evo 2.25". Did 30 km around lake legs, 1st with wheelset having RR's in ghetto tubeless, 2nd in FF's with tubes and little later 3rd with 1st wheelset but FF's in true tubeless (Stans tape, sealant and tubeless valves).

All laps in about same average HR. Weather was gusty winds, calming rain, and 1st & 3rd were matching, 2nd was maybe little easier. Laps 1 and 2 went inside 60 seconds time, but 3rd was about five minutes faster. Also riding bike path underways and following inclines FF's are keeping momentum like road tires, RR's were killing speed way much more.

As this test had most of it in tarmac, I headed to my two past racing courses. For both I rode matching lap times as my best with RR's in actual races.

Because weight distributes 38% front 62% rear, ideal calculated pressure is 1.15 bar front, 2.17 bar rear. Having DT-Swiss XR-400 rim @ front was ok with ghetto tubeless Racing Ralph tires @ 0.9 bar, but I dropped pressures twice with Furious Fred.

Then realized that 1st wheelset built for this bent were using WTB LaserDisc rims which have sort of bumps to keep tires beaded better. I rebuilt WTB rims with WTB LaserDisc Lite hubs and put FF's on top. Seems to stay beaded way much better.

I have to say I feel sorry about not doing these tire testings way earlier. I could stay with top guns in both of those races with FF's. And have steam to spare for going even faster...

Before WTB rims I participated to 120 km MTB event and broke stem, again. It was built from aluminium stem, cut, welded mild aluminium tubing as extension in between. Later replaced first part with saddle post which was total failure. It fractured during that event and after 10+ km of serious off-road action snapped loose. I had to DNF from 1st pit area.

Next day welded together new stem setup from steel original. Now it doesn't fracture, it may bend but steel is steel.

Current weight with way much lighter tire setup and all other optimization was scaled 19.0 kg.

Cheers,
-Mika

Diy bents: Full-suspended off-roader @ 2012, Vendetta clone @ 2012
Commerials: MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
mhelander Posted - 06/17/2013 : 22:18:05
quote:
Originally posted by warren

Wow, that was incredibly rocky. Have you tried running your videos through the youtube image stabilization filter?



Rocky it is, but quite smooth to ride as seen in my steering effort and minimal braking needs.

Yes I tried YouTube filter. It made blurry video even worse and removed rocky accent I wanted to retain in that short downhill clip.

I'm heading today to XC course and record that if weathers co-operate. Same camera and likely cloudy weather. But I'll try both YouTube and and some other non-clould stabilization filtering as clip will be way shorter, 6-7 minutes.

Cheers,
-Mika

Diy bents: Full-suspended off-roader @ 2012, Vendetta clone @ 2012
Commerials: MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
warren Posted - 06/17/2013 : 13:29:08
Wow, that was incredibly rocky. Have you tried running your videos through the youtube image stabilization filter?
Speedbiker Posted - 06/17/2013 : 07:33:40
Great, now I have to build another bike!
mhelander Posted - 06/17/2013 : 02:07:43
Warren, you're so right. I finally spent some time adjusting my fork and rear air shock rebounds and now it rides so much better.

Couple of videos:

I was faster in full course despite riding in moderate pace, making couple of mistakes and one longer off-course, than any racing laps. Seems practicing and fine-tuning this bent is paying off.

Cheers,
-Mika

Diy bents: Full-suspended off-roader @ 2012, Vendetta clone @ 2012
Commerials: MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
warren Posted - 06/06/2013 : 05:48:07
Hi Mika,

Yes, there is nothing like a good air shock. I had a lot of handling issues with non dampened spring style rear shocks, but the air shocks with adjustable rebound work well to keep the rear wheel on the ground over bumpsa and around the bumpy corners.

-Warren.
mhelander Posted - 06/05/2013 : 22:50:13
Thanks Warren, that's what I do when have composite stuff purchased and time to spare.

Meanwhile using hammer and partially fixed TIG-handle fixed current broken pivot. Then using thread locking compound and plenty of time without shock and seat to adjust all in pivoting for free movement without any binding or non-designed movement.

Now it works as expected and lasted well 40 minute and 11 km riding hard in XC race, including transfer to race area and back. Beating was little too much for my wheelset, loose spoke squeaking @ rear, otherwise everything went well. And I need to experiment with shock rebound adjusting as now I got plenty of course mistake caused suspension oscillation which kept me extra busy.

Cheers,
-Mika

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

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