GCinDC's Giant DH Comp

[Duc998]

GC what chainring are you getting? I want at 46T and up. Basically I like pedalling even at speed . But being a noob unsure what will fit.

[GCinDC]

GC what chainring are you getting? I want at 46T and up. Basically I like pedalling even at speed . But being a noob unsure what will fit.

i meant to see if a front derailleur would even work on the bike. i'm not sure.

my current ride is effectively a 3 speed: i can change the front from 44T to grandma gear, and the rear freewheel is a 7speed 11t-32t, but the derailleur is only a tensioner, and i removed all the cables. that's the only way i know of to have an 11T in the back, and can pedal up to 35mph. for off road stuff, i can drop to second gear, and if power dies, i can drop to the grandma gear and still pedal uphill.

so part of the answer depends on how i want to ride this. if commuting mostly, i'd like to duplicate the setup and:
- install 7cog 11t rear (now smallest is 14t)
- remove rear derailleur cables, shifter from right handlebar, where it no longer fits because of throttle
- add front derailleur and shifter for left handlebar side
- add front chainrings, which i know are 4 bolt, and i presume is "104mm", and doing some quick searching, there's definitely the bell curve on price appears to be on the mid-40ts:

when searching "4-Bolt 104mm 50t (and up)", i get no hits, but when i drop down to "4-Bolt 104mm 48t" there are options between $32 - $80 for a single chainring..

so anyway, yeah, i'm kinda in the same boat.

and i'm going away for the weekend so i won't be able to work on this at all!

i almost taped the battery pack on to ride in with it this morning but fell asleep at 8:30 last night.

[Alan B]

I have a crankset that has planetary gears and 110mm chainring mounts. It provides 1:1 and 1.6:1 selectable gearing, making your chainring 60% bigger, or straight through. With this you can use the singlespeed 16T freewheels and still get high speed pedaling with a reasonable chainring, and avoid the derailleur altogether. The original units are spendy but this Taiwan licensed Schlumpf unit was about half the cost and takes standard chainrings and crank arms.

[GCinDC]

I have a crankset that has planetary gears...

link? thx, g

[nieles]

http://www.schlumpf.ch/hp/schlumpf/antriebe_engl.htm

http://www.schlumpf.ch/hp/sd/sd_engl.htm

[Alan B]

I got it from Accountant, I haven't found a link to it. Lets see if I can find a photo.



This photo was to show the shipping damage, it has been repaired. One of the five ears was bent, it is a punched steel part that straightened out well. I'll have to take new photos. You can see the end of one of the cranks in the background. It is a licensed variation of the Schlumpf speed drive crankset with standard 110mm spider for chainrings and standard crank arms. It shifts by tapping the button in the center of the crank with your heel, one way for 1:1 and the other way for 1.6:1. Perhaps Zombiess will be carrying these, I don't know. I'm planning to put it on my Greyborg. I ordered a chainring and short bolts for it this morning. I need to choose some pedals and get the chain and freewheel for it.

[Alan B]

http://www.schlumpf.ch/hp/schlumpf/antriebe_engl.htm

This lower cost sub-licensed model is not shown on the Schlumpf websites. It is similar but the design has been adjusted for lower pricing.

[nieles]

their site is a bit weird to navigate.

i added a page with more versions of the drive.
is it pictured on the 2nd link in my previous message?

[gensem]

You guys are searching for the wrong name...
Ask zombies because im sure he has more info.

[binlagin]

I want a knockoff schlumpf!

[adrian_sm]

when searching "4-Bolt 104mm 50t (and up)", i get no hits, but when i drop down to "4-Bolt 104mm 48t" there are options between $32 - $80 for a single chainring..

so anyway, yeah, i'm kinda in the same boat.

I got a 52T that I have been really happy with, from Rennen Design for $40 + shipping.
viewtopic.php?f=6&t=17944&p=343636&hilit=chainring#p343636

[Alan B]

I posted new closeups of the Schlumpf variant gear drive crank on this thread:

viewtopic.php?f=3&t=34929&p=539616#p539616

[kfong]

Greg, just ran across this on Keyne's DH build. Might as well coat it with something that cools as well. Big concern is how temperature tolerant is the stuff. What's the max heat range and where can we get some



Furthermore, if you want to further improve heat transfer within the motor then you pot the stator winding using a thermally conductive epoxy instead of the traditional "varnish" still used in most AC induction, stepper, and low performance BLDC motors. 15-years ago I began potting BLDC stators using a thermally conductive epoxy and this is becoming standard in high performance BLDC motors since the improvement in heat transfer is 40-50% higher compared to using a varnish! If you want to read more about potting then obtain a copy of my paper I presented at the 2006 SMMA Fall Conference in Saint Louis MO, "How to Increase a Motor's Continuous Torque Output and Power Density by Potting its Stator With Thermally Conductive Epoxy".

In addition, I have published companion papers in two different motor industry trade magazines, Sept. 1, 2009 issue of "Energy Efficiency & Technology" and Aug 1, 2009 issue of "Motion Systems Design (MSD).

Richard Welch Jr
Consulting Engineer - Oakdale, Minnesota USA

[GCinDC]

finally got the pack roughed in with the handle/lock loop.

pack_closeup.jpg (91.76 KiB) Viewed 840 times

funmachine.jpg (114.1 KiB) Viewed 840 times

also got in a quick test drive.

80v of fresh lipos.

maybe after another drive or so, i'll be able to decide about an 18x3 motorcycle tire...

[Duc998]

wow GC that looks great, Its neat compact and stealthy. If you have time can you take some more close up picks of your pack? Also some front / rear shots I want to get a feel how wide the box is.

Also whats that your using to cover the wires? Dam I just want to steal all your ideas

Cant wait for mine. Hopefully will get the box done this week...

[gensem]

looking really good... good caster angle for speed...
ytube?

[GCinDC]

If you have time can you take some more close up picks of your pack? Also some front / rear shots I want to get a feel how wide the box is.

your wish is my command:

nothing special at all - i want to be sure i like parts where they are before doing them better, if i ever get to that... it'll be nice lunchbox to carry in the elevator, but there's not a lot of contact area with toptube, just a cut off corner really, and for the triangle fit, i might prefer it be a bigger triangle - and i might put connectors there after all. the aluminum connector mount i fabbed up is totally half ass, and you can see the wires pop out more than i'd like....

oh, i'm using ebikes.ca stretchy sleeve to cover the wires in a couple places - is that what you're asking about? i highly recommend it! (store> parts > Connectors & Misc. Parts)

firstcommute01.JPG (133.04 KiB) Viewed 644 times

i rode it into work too. felt a bit blind w/o the CA, which i should have put on - and i wished i'd warmed the lipos up in the garage first!

but it's raging. it loves the grass and dirt. i can't wait till quitting time!

i was sooo late, i didn't have time to mount a gopro.

and i'm not even sure how i feel about the bike yet! some reflections:
- it's smaller than i'd like for sure; i feel a bit scrunched
- when i stand, i'm so much further forward that a nasty regen burp would eject me. wrist position is not ideal
- gotta move the seat back for starters - feels like a chopper w/ ape hangers compared to the GT
- riding the road w/ nobbies is weird too - i don't plan to do so much but love them in the rough after stuck w/ slicks for street for so long
- mid-suspension stop is still a bit weird but will play w/ too, if not change straight away. sag might be about 3" right now. curious how 500lb spring feels...
- left the wife alone w/ three kids for the better part of saturday and paid bigtime sat night/sunday.. and still so much to do!

[Hyena]

oh, i'm using ebikes.ca stretchy sleeve to cover the wires in a couple places - is that what you're asking about? i highly recommend it!

I've used inner tube to achieve a similar result. yeah yeah I know, another recycled use for them

left the wife alone w/ three kids for the better part of saturday and paid bigtime sat night/sunday..

Don't I know about that all too well!
I also had the opposite on Saturday, the wife had a baby shower so took the 2 kids with her and I had the afternoon to myself for the first time in months. And what happened ? It absolutely bucketed down so I couldn't go riding

[GCinDC]

[grindz145]

Haha! Nice! So you want a motocross bike wheel eh?... No idea why...

[dbaker]

Nice video

[Duc998]

wow nice GC thank you so much for the vid's, Love it your pack in nice and compact. Bike looks stealthy too really appreciate it thanks mate.

Loved even the last bit with your kid on the bike, Something I'd like to do take the kids for a quick ride. Did u make something for them to sit on?

[deecanio]

Hi Greg,

You could give yourself a bit more cockpit room with a laid back seat post, used to use them back in the day for bmx but im not sure if they do them for mtb size, quick look sais they do various sizes but if they dont you could always mod/make. example.......
http://www.cycleking.co.uk/searchpage.p ... 022mm%20CP
you'd need a saddle that has adjustable clamp but could give you more space?
will have to wait till i get home to check the vid.

D

[GCinDC]

You could give yourself a bit more cockpit room with a laid back seat post

cool. thanks, D!

woahnelly.jpg (73.04 KiB) Viewed 533 times

you'll see in the second jump that the bottom fell out on me. not sure if it some dirt caved in on the top ledge (which was easily 3', btw, even tho it only looks like 14"), or the extra motor weight i'm not used to. i usually always try to land evenly on two wheels. and if i was on pavement, i would have surely wiped, cause when the bottom dropped, my grip caused the throttle to rev and it tried to buck me when i landed. not used to the grip of the fat ass cheapo chinese throttle, which i should have swapped with my magura...

the handling is way different, and that SPV on the rear shock freaks me out. it feels like i'm riding a little motorcycle with a blown rear shock that's always bottoming out.

i hate to say it, but if i can't sort that out, this will just be another interim bike before a phasor or stealth or homebrew... sad to say it so early, but i should definitely have held out for a Large frame... i'm going to try to do a comparison of the GT frame, just for my own curiosity, to compare foot, seat, handlebar geometry. if the ground were angled at 30 degrees, however, as in DOWNHILL, the ergonomics would feel a lot better...

for street combat right now, i'd take the GT without question. but this is probably just the normal process of adjusting to a new frame.. i don't like that SPV, even after more adjustments, but i gotta say, i go off curbs and hardly feel it. and i was running over some rocky stuff and the rear was so soft i thought the tires were low, but they weren't. oh well, it's a fun process - a journey of discovery - and riding in i was musing about the names they came up with for these bikes... Transition Dirtbag. of course the Stinky...

[kfong]

I noticed mdd0127 selling just an 18" frame, not sure how much different that is size wise.
http://www.endless-sphere.com/forums/vi ... =9&t=37461