Giant DH-team offroad build. R&D thread

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Re: Giant DH-team offroad build. R&D thread

Post by Alan B » Apr 20 2011 11:54am

The Magura throttle with resistors to spread out the control to the full range is very nice. Far less sensitivity so less problem. Largely it is learning, this skill (actually lack of) is immediately appreciated when stepping up in motorcycles, after awhile it is automatic and natural to isolate the motion from the wrist angle.

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Re: Giant DH-team offroad build. R&D thread

Post by Drunkskunk » Apr 20 2011 12:48pm

LegendLength wrote: I'm using a kona stinky (below) which isn't technically a DH frame but is close enough .....
Not that it matters much, but when your Stinky was designed, it was a true DH. Kona downgraded the Stinky name when they started to produce better bikes, but your bike should have been sold as a DH. Its a 2004, right?


Good looking bike. I think the Stinkys are taking over as bike of choice for Ebikes.
Buy the ticket, take the ride.
Monster Bike:http://endless-sphere.com/forums/viewto ... =6&t=38667

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Re: Giant DH-team offroad build. R&D thread

Post by manitu » Apr 20 2011 2:32pm

Yeah , both my DH-team and your stinky got replaced by newer bikes with an inch more travel and a degree less head-angle.
They're now in the "freeridebikes wich are to heavy to pedal uphill" category. :D

Yeah , I have seen posts about calibrating the magura throttle. But that is still some time ahead.


What counts now is :
Clyte HT35
Lyen's 12x4110 modders edition.
about 80v 15ah lipo (Lyen said max 88v max nominal with out further mod's)

This package should get me up most hills , I guess.
Just need to be absolutely shure I've chosen the right motor. then order my stuff.
About that.. ther were some indications that the european version differs from the US version.
Does this look like the same as you have over there?http://shop.crystalyte-europe.com/produ ... 295&page=1
there is some pdf's wit dimensions and data.


.manitu

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Re: Giant DH-team offroad build. R&D thread

Post by keyne » Apr 20 2011 3:57pm

Why don't you go for an 18fet controller? Then you have scope to bump up the current more easily later if you want. Definatly Crystalyte HT/HS35 over 9C. Fitting brake switches isn't that hard, I'll put up some pics - reed switches + tiny rare earth magnets.

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Re: Giant DH-team offroad build. R&D thread

Post by manitu » Apr 21 2011 1:19am

I'm going for most bang for my bucks . both the HT35 , Lyen 12FET , and cheap lipo's seems to fit that category. I see some reports of issues with the 18FET too , I'll let the pro's iron out the design first. I don't think this is going to be my last build , so plenty of time to scale up later . If the equip survives until I want something better , I'll pass in on to a friend. By then I'll have a much better picture of what I want , and what setup will suit my needs.

I might buy another motor when I've finished the bike , most likely a HS35. One rear wheel for off-road , one for track days. Guess I'll will feel the need for a bigger controller then...

.manitu

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Re: Giant DH-team offroad build. R&D thread

Post by MadRhino » Apr 21 2011 2:47am

manitu wrote:Guess I'll will feel the need for a bigger controller then...
My guess, is that you'll feel the need for a bigger motor too, soon :twisted:
Make it fool-proof, and I will make a better fool.
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Re: Giant DH-team offroad build. R&D thread

Post by grandmasterE » Apr 21 2011 3:08pm

I don't know if you're aware of this, but those Giant bikes have non-standard rear axle dropouts. 'Normal' is 135x10 mm, these are 150x12 mm. May not be a problem for you, but I hadn't seen mention of it in your thread so I thought I'd bring it up. Just something to consider.

E.

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Re: Giant DH-team offroad build. R&D thread

Post by manitu » Apr 21 2011 10:08pm

I've noticed the dropouts , it's actually a 12x135mm maxle, only the 2005 model and replacement swingarms are 12x150mm.
It's the same design as the 20mm front maxle.

I'm not shure what I'll do with the dropouts.
This one http://endless-sphere.com/forums/viewto ... =6&t=15439 has welded dropouts.
Doc's DH-comp has custom made plates with dropouts glued(!) to the swingarm.http://endless-sphere.com/forums/viewto ... 3&start=60

I would like to have clamping dropouts , so I guess I'll have to get two plates machined.
ImageImageImageImage

The left side is easy , just mill down the elevated area on the outside and put a steel plate on the outside. the right side however..

.manitu

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Re: Giant DH-team offroad build. R&D thread

Post by manitu » Apr 23 2011 12:36am

Still not shure what to do about those dropouts. Would prefer not to weld , as the frame is made from aluxx sl , basically a 6000 alu , with added copper. It's supposed to be heat-tempered and quench-cooled after welding , wich would mean a new paint-job.
Pictures: The frame and swingarm design.
Image Image

Here you can see the linkage wich drives the shock. Nice and progressive through the first part of the travel.
Image

Some parts for the project:
Image
The telescopic , remote controlled seatpost is genious . just adjust it for pedaling in the top position , the drop it for offroading.
Image
Forks.I'll use the 888RV for the mock-up , but I'll change to the 888RC2X wich is currently on my nomad, when it's time for test-riding. I'll be testing the bike with the RS Lyric too , just to see how much the high-speed shimstack improves the handling. If it's significant , I'll drop a AVA cartridge in that 888RV.
Image

.manitu

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Re: Giant DH-team offroad build. R&D thread

Post by zzoing » Apr 23 2011 6:23am

here are my main considerations for my next atb ebike build:
a squishy suspension, upright riding, cheap 2nd hand long travel ebay bike. adjustable handlebars, front forks upright for riding no hands for touring, second thumb throttle under the saddle for no hands, battery in aluminium tailored box attached to seat post tube rack-bar (20 dollar on ebay) so that the wheel can spring around half way into the space in between the 2 battery halves. i like having no weight on the front of the bike as you can pivot the front really fast and lift it, but im interested to try a XC bike with a battery on the downtube also. squishier suspension makes it twice as comfy on trails than a pro DH bike:)


1> you would save much money by getting a used giant/kona/marin etc bike from ebay for 350 dollars, seeing as it will get bracings etc that will damage the paintwork. the frame you have is great, i want it, the dropouts are weird i dont see where the axle goes. So dont mill that brand new bike, mill an old one and sell that one.

2> DH is ok but i did 2000 miles on a GT bike and the leaning forwards posture messed my back up. if only i had known about yoga back stretching where you hang upside down i would have a much better back now. if you compress your disks, stretch them pefore bedtime. So get a bike with shorter wheelbase, higher handles, handles close to saddle as poss. i was carrying 100kg logs prior to that gt bike! not any more. a good quality adjustable handlebar that tips towards the rider can be great.

3>squishy soft suspension is good for an ebike because you are not doing 2 foot drops on it, you would probably just do crosscountry. and for woods and tracks, soft is more comfortable.

4>9c is millions of times better than Xlyte 406 etc, the torque is great, it makes abit too much noise, it isnt centered properly, it can climb 600 meters from cold before overheating, it's light, its hard to respoke cos of dishing, i need 2 spoke lengths, torque and low rpm noises are the most pleasant thigns with XC, 9c has good torque and noise at low rpm.

5>i would get a ping 48v battery, or a 10ah 40 amps battery if you can find one that lasts a couple of years... i would get a ping 48v 20ah, and fasten it using a standard atb seat post rack pole in a custom box. devide the ping in 2 halves and put one on either side of the back wheel, about halfway level with the tyre, as close to the seatpost and as low down as they go so that they dont interfere with feet or hit the suspension bar when it rises, else you can put one half of a ping at the back over the wheel and the other in the frame, either way you would have to rewire it longer.

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Re: Giant DH-team offroad build. R&D thread

Post by manitu » Apr 23 2011 6:54am

Might work for you but not for me. A slack head-angle is essential for handling at speed , even if it makes it impossible to ride without hands (I'll keep my throttle on the handlebars) If you put all your batteries to the rear , you'll have to move over the handlebars when cornering in the dirt to keep the front wheel from loosing traction.
Where did you get the impression that XC bikes have softer susp than a DH-bike??

1: Yeah , a used bike would probably be chaper , but this one has been lying on a shelf in the shop I work in since 2004 , I get it cheap , like paying full price for the shock , frame for free.

2: Most DH bikes got short headtubes , this one is no exeption. Short wheelbase is not a good idea for the speeds these bikes can do at 72v.

3: Suspension depends on speed and terrain: Squishy soft susp is a BAD idea if you plan on fast off-road riding with a hub motor in the rear. The suspension is for sticking the wheel to the ground , not your ass to the seat. Just for strolling along fire-roads and on-road riding in moderate speeds , I guess it would work fine.

4: I'm not getting a clyte 4xx , but a clyte HT35 . Totally different motor

5:No ping here . 72v 15ah Lipo. I'll have to get the bike under 88lbs (european regulations)

.manitu

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Re: Giant DH-team offroad build. R&D thread

Post by LegendLength » Apr 23 2011 9:02am

manitu wrote:3: Suspension depends on speed and terrain: Squishy soft susp is a BAD idea if you plan on fast off-road riding with a hub motor in the rear.
Would you mind expanding on that? I have set my rear shock to be as soft as possible without bottoming out (with the extra weight of the batteries). Should I be setting it harder?

I want it to be good for 20 - 25 mph off-road where you sometimes come across bumps at speed.

Or by 'squishyness' are you referring to the rebound rate rather than the spring stiffness? My only adjustment on the old kona is turning the spring which makes the spring longer or shorter (or buying a spring with a different rating).

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Re: Giant DH-team offroad build. R&D thread

Post by manitu » Apr 23 2011 10:50am

@legendlength: If all you can adjust is the spring , you should just set the correct sag and be done with it.
The spring only supports your weight and pushes the wheel out after a hit. The damper controls the motion/traction of the wheel.
The weight of a hub-motor (and high speed) calls for a much firmer compression damping than a normal mountainbike.

I'm in the process of doing a write-up on suspension settings here : http://endless-sphere.com/forums/viewto ... =2&t=27149

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Re: Giant DH-team offroad build. R&D thread

Post by zzoing » Apr 24 2011 11:32am

Some mountain bikes are made to take 5 -10 foot jumps and the equivalent of 250 kilos at least, That is why i say that alot of rear suspension is too stiff for a bike with a motor on it, and you cant have too responsive a suspension on a pushbike because it absorbs the pedal power. you dont need that on a mountain e-bike, you arent pedalling up hills with it. I dont know much about how soft vs hard suspension, the different makes and models and adjustability, but i do know that if you aim for comfort rather than 10 foot jumps, those 10 miles of rocky terrains will feel alot better. (isnt it possible to have 2 suspensions in one, one squishy and one harder?). I was bombing it along clear tracks and grassy areas with hills, 50kph is abit dangerous if there are rocks and bumps and you dont know the track.

A mountain bike is always goint to have stability, the wheel base will be the same give or take 4-6 inches, if you and up doing 3 hour rides crouched down for months on end you will prefer being able to sit upright.

The angle of the fork is the same, i dont mean way up vertical, just i am noting that i love doing miles with no hands going nice and slow and so that is essential for me. I dont think the difference in angle between bikes makes them more agile for you once i you totally tuned to the bike as regards riding with handlebars, the most important for me is comfort rather than speed on tracks. i dont think i can bomb it very technically with a 25 kg frame. :o

Placement of the weight is all the art in building a responsive bike as it is the biggest dilemna. it makes the riding style completely different. best is centre it in the crank but that is impossible. at the back makes for a weird bike. you can pivot on the back wheel and you can make fast adjustments to the front but the back becomes an elephant. in the middle i dont know, but if there is too much weight to move the front wheel fast i think that is a mistake. like more than 2kg transferring to the handlebars is clumsy imho.

The fast turns are not really possible on a heavy frame mountain bike, the wheels grip less, they are half as responsive, the frame is half as responsive, if it goes out of line you have no chance of pulling it straight again, especially if the handlebars are heavy, because the frame is abit of a dead wheight, it carries on wherever it is sliding you cant cruise through bends very safely on one.the centre of gravity of the frame is high, etc etc. but that is just my i have a long distance bike, i went up a 1400meter hill recently.

if you are doing tracks and the bike is 72v, i think it is good of you to align yourself with EU law in that the frame must be lighter than the maximum, as that is quite an engineering feat to achieve. i have a 10kg ping and 7 kg of motor etc. as my first ebike weighed 35 kilos from china i didnt know about the wehight limit.

the motor weight doesnt affect the suspension as it has no suspension. the battery and the rider only do. I dont know about the classifications of dh/xc/trail/etc bikes, i meant xc as in mountain bike.
Last edited by zzoing on Apr 24 2011 11:56am, edited 3 times in total.

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Re: Giant DH-team offroad build. R&D thread

Post by Alan B » Apr 24 2011 11:48am

What is the EU weight limit?

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Re: Giant DH-team offroad build. R&D thread

Post by zzoing » Apr 24 2011 11:55am

40 kgs / 88 lbs. enough for a 18kg battery and a 5kg motor :)

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Re: Giant DH-team offroad build. R&D thread

Post by Alan B » Apr 24 2011 12:17pm

zzoing wrote:40 kgs / 88 lbs. enough for a 18kg battery and a 5kg motor :)
If the battery is easily detachable it might not be counted, or one could have a "light" battery and a "longrange" battery so only the light one would have to make the weight??

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Re: Giant DH-team offroad build. R&D thread

Post by manitu » Apr 24 2011 7:05pm

Some mountain bikes are made to take 5 -10 foot jumps and the equivalent of 250 kilos at least, That is why i say that alot of rear suspension is too stiff for a bike with a motor on it, and you cant have too responsive a suspension on a pushbike because it absorbs the pedal power. you dont need that on a mountain e-bike, you arent pedalling up hills with it. I dont know much about how soft vs hard suspension, the different makes and models and adjustability, but i do know that if you aim for comfort rather than 10 foot jumps, those 10 miles of rocky terrains will feel alot better. (isnt it possible to have 2 suspensions in one, one squishy and one harder?). I was bombing it along clear tracks and grassy areas with hills, 50kph is abit dangerous if there are rocks and bumps and you dont know the track.
The probem here is'nt big jumps vs comfort , it's GRIP vs comfort.
And the problem here isn't the weight on the bike , but the weight on the wheel (including the motor) wich is accelrated upwards when you hit a bump. If you have to soft compression settings here , the wheel will not be able to follow the ground , but is trown into the air. The weight of the motor makes for a massive increase in force wich needs damping, hence the harder compression setting. If this takes some of the comfort away , so be it.
A mountain bike is always goint to have stability, the wheel base will be the same give or take 4-6 inches, if you and up doing 3 hour rides crouched down for months on end you will prefer being able to sit upright.
The point on the front wheel wich touch the ground is right under the axle. But the axis wich the wheel turns around will touch ground in front of this. As the distance between these two moints increase , so will the leverage of the bike's weight , trying to tip the wheel to either side.
This means that at a lower head angle you'll have to go faster for the gyro effect of the wheels to be strong enough to keep the front wheel upright.
The angle of the fork is the same, i dont mean way up vertical, just i am noting that i love doing miles with no hands going nice and slow and so that is essential for me. I dont think the difference in angle between bikes makes them more agile for you once i you totally tuned to the bike as regards riding with handlebars, the most important for me is comfort rather than speed on tracks. i dont think i can bomb it very technically with a 25 kg frame. :o
A raked out fork makes a more stable ride, bigger turning radius, and the steering response , being slower, is well suited for higher speeds.
Steep forks give a zippy, fast reacting ride with smaller turning circle , well suited for slower speeds.
Placement of the weight is all the art in building a responsive bike as it is the biggest dilemna. it makes the riding style completely different. best is centre it in the crank but that is impossible. at the back makes for a weird bike. you can pivot on the back wheel and you can make fast adjustments to the front but the back becomes an elephant. in the middle i dont know, but if there is too much weight to move the front wheel fast i think that is a mistake. like more than 2kg transferring to the handlebars is clumsy imho.
Yeah , weight distribution is important a bike /e-bike . But you need weight on the front wheel!! No weight equals no grip!
Allso remember that the sentrifugal forces pull your bike outwards , exactly at the CoG.
I once had a Hond MT5 50cc road legal bike , with allmost no weight on the front. It was downright dangreous to drive in the woods or on wet roads. You had to sit on the fuel tank to get grip on the front , wich felt dangerous and unnatural.
The fast turns are not really possible on a heavy frame mountain bike, the wheels grip less, they are half as responsive, the frame is half as responsive, if it goes out of line you have no chance of pulling it straight again, especially if the handlebars are heavy, because the frame is abit of a dead wheight, it carries on wherever it is sliding you cant cruise through bends very safely on one.the centre of gravity of the frame is high, etc etc. but that is just my i have a long distance bike, i went up a 1400meter hill recently.
Fast turns not possible? No difference in what's possible with a 40 kg e-bike and a 40 kg dirtbike. A eventual hub motor will limit the e-bike a bit , but hey , thats my point here in the first place.
the motor weight doesnt affect the suspension as it has no suspension. the battery and the rider only do. I dont know about the classifications of dh/xc/trail/etc bikes, i meant xc as in mountain bike.
This is outright wrong , see at the beginning of this post.

*edit: Oh , anotherting 18kg ping?? my frame WITH battery will be around that weight.
.manitu

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Re: Giant DH-team offroad build. R&D thread

Post by Mark_A_W » Apr 25 2011 5:34am

Just some points from skimming through this thread:

1. Twitchy throttle over bumps: A half grip throttle is best here, you can hang on with your little fingers and actuate the throttle with finger and thumb. A trigger throttle would be good too, assuming you can get it to work with brakes and gears (hint, a grip shifter on LH bar works well).

2. Welding mods: My rear end is welded solid, then cut creating vertical dropouts plus 6mm stainless torque plates. Welding does anneal the area, but I haven't had any trouble - there's just so much metal there. The danger area is the end of the welded zone, but again, it's HUGE.

3. Handling at speed: With 2002 Bomber Junior T's up front, and a stiff rear spring (a 600 I think), my bike is rock solid at 80km/h (steep downhill). That's the best thing about the DH-Team/Comp frame- it's totally solid, no rear end wobble - makes for predictable handling...and you can fit batteries. Dr Bass has done over 106km/h on his remember. It's not at all twitchy like a XC dually - they are not meant to go fast.
Under construction: Giant DH Team, MAC Shanghai, Infineon 18 FET controller, 64v Headway battery. LINK!!

Retired: Kona Dawg Dually + Bomber Triple Clamp forks with Nine Continents front hub motor, 48v 10Ah Headway LiFePO4 Pack + 12v 10Ah Headway LiFePO4 booster pack (nominal 64v).

Powered by the sun :)

Dead: Jamis Dakar frame, Mongoose Pro Downhill frame, cooked Lipo booster pack....and various other bits and pieces...

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Re: Giant DH-team offroad build. R&D thread

Post by manitu » Apr 25 2011 10:07pm

@Mark_A_W :
You mean , you welded the axle holes and clamp? Not the steel to the aluminum?

I've been thinkin about either welding the axle hole and clamp and grinding 10mm vertical dropouts , or grinding out vertical dropouts from the axle hole , 14mm wide. either way , I'll use steel torque-plates on the outside.

But those dropouts are like 12-13mm thick! + the gearhanger on the right side.. So:135mm wheel + 25mm dropouts + 6mm gear hanger + 2x5mm torque plates + a shim to make space for a 7 or 9-speed freewheel an maybe load-spreading shim on the other side to , say 3mm total.
That's 179-180mm of a 195mm axle.. Something has to go , at least 5-10mm.

The torque-plate will have a torque arm up between the chainstay and the seatstay + two bolts into the plates around the axle. I think..

Thanks for the input , Whithout the people on this site , I woldn't have started this build at all.

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Re: Giant DH-team offroad build. R&D thread

Post by zzoing » Apr 27 2011 6:24am

80km/h (steep downhill).

Woah serious ! downhill on the road or in some praries? I suppose i dont bomb it around then, it's so pretty going up and down rocky mountain paths and through woods, i only bomb it when i know for sure there arent any holes and sudden turns. Fields on top of hills are great albeit so bumpy, i like to have soft enough suspension that i can go over all the hardened cow treads without my bike acting like an earthquake zone. The best tracks i found had about 20 1meter deep hillocks, it would go up and down just like an amusement park at top speeds. I thought it was all about comfort, i do recall that the front wheel felt too light when bombing and turning at speeds, but i think that is because i had small hybrid treads and it when it was very wet and slippy. it's pretty good having a light front doing very technical slower rides across rocks and stuff where you have to choose the path very exactly. it's a tradeoff. either precise for slow technical stuff or stable turning at speeds. either comfy enough to race over cobbles and rough rocks or stiff, i do think the 7 kg motor will respond very fast even with a soft rear that is tuned to carry a 65-70kg guy.

if you do 80 kph, on a bike... that's insane man!!!

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Re: Building a offroad commuter bike

Post by bigbore » Apr 27 2011 12:57pm

Alan B wrote: The Cycle Analyst has current and speed limiting but only one setting. I believe there is a way to limit against an external input which could be a switched signal, but I have not looked into that.
Seriously? An external input on the Cycle Analyst which could be a switched signal would be perfect for the e-bike I would build. Anybody have done it?

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Re: Building a offroad commuter bike

Post by Alan B » Apr 27 2011 1:54pm

bigbore wrote:
Alan B wrote: The Cycle Analyst has current and speed limiting but only one setting. I believe there is a way to limit against an external input which could be a switched signal, but I have not looked into that.
Seriously? An external input on the Cycle Analyst which could be a switched signal would be perfect for the e-bike I would build. Anybody have done it?
It is covered in the manual (which you can download from the web as I recall). They show a potentiometer, but a switch could select between several values. This input can be used to limit either speed or battery current (power). In my manual it is section 9.2 page 19.

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Re: Giant DH-team offroad build. R&D thread

Post by manitu » Apr 27 2011 5:53pm

zzoing wrote:80km/h (steep downhill).

Woah serious ! downhill on the road or in some praries? I suppose i dont bomb it around then, it's so pretty going up and down rocky mountain paths and through woods, i only bomb it when i know for sure there arent any holes and sudden turns. Fields on top of hills are great albeit so bumpy, i like to have soft enough suspension that i can go over all the hardened cow treads without my bike acting like an earthquake zone. The best tracks i found had about 20 1meter deep hillocks, it would go up and down just like an amusement park at top speeds. I thought it was all about comfort, i do recall that the front wheel felt too light when bombing and turning at speeds, but i think that is because i had small hybrid treads and it when it was very wet and slippy. it's pretty good having a light front doing very technical slower rides across rocks and stuff where you have to choose the path very exactly. it's a tradeoff. either precise for slow technical stuff or stable turning at speeds. either comfy enough to race over cobbles and rough rocks or stiff, i do think the 7 kg motor will respond very fast even with a soft rear that is tuned to carry a 65-70kg guy.

if you do 80 kph, on a bike... that's insane man!!!
a moth ago , I was in Spain , riding the dowhill-slopes in Malaga , Granada and Marbella with some cracy swedes , training downhill. One of the swedes had a crash in Granada, where he tumbled for well over 150 feet , before he stopped. Dont know the speed but he was going FAST!
I'll upload somer pictures later , have to find the cable for the camera.

Anyway , wont bee to much around for the next week or two. the snow is gone from the roads , and the tire changing season is here . 15 hour days at work.

.manitu

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Re: Giant DH-team offroad build. R&D thread

Post by Mark_A_W » Apr 28 2011 5:30am

manitu wrote:@Mark_A_W :
You mean , you welded the axle holes and clamp? Not the steel to the aluminum?

I've been thinkin about either welding the axle hole and clamp and grinding 10mm vertical dropouts , or grinding out vertical dropouts from the axle hole , 14mm wide. either way , I'll use steel torque-plates on the outside.

But those dropouts are like 12-13mm thick! + the gearhanger on the right side.. So:135mm wheel + 25mm dropouts + 6mm gear hanger + 2x5mm torque plates + a shim to make space for a 7 or 9-speed freewheel an maybe load-spreading shim on the other side to , say 3mm total.
That's 179-180mm of a 195mm axle.. Something has to go , at least 5-10mm.

The torque-plate will have a torque arm up between the chainstay and the seatstay + two bolts into the plates around the axle. I think..

Thanks for the input , Whithout the people on this site , I woldn't have started this build at all.
Yep, the axles holes and clamp are welded, the torque plates bolt on. I didn't do it, a bloke named Kurt did it for Voicecoils - read through my thread (link in signature).

And yep, you need a wide axle motor. Crystalyte or BMC/MAC. And with a 205mm MAC axle, I can't fit spring washers, just the nuts (I HAVE to use Locktite).
Under construction: Giant DH Team, MAC Shanghai, Infineon 18 FET controller, 64v Headway battery. LINK!!

Retired: Kona Dawg Dually + Bomber Triple Clamp forks with Nine Continents front hub motor, 48v 10Ah Headway LiFePO4 Pack + 12v 10Ah Headway LiFePO4 booster pack (nominal 64v).

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Dead: Jamis Dakar frame, Mongoose Pro Downhill frame, cooked Lipo booster pack....and various other bits and pieces...

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