Puma power..

[j3nks]

Hi all..
Been hanging around trying to gather info for a while..
now it's time to start my project..

Nothing spectacular..
A puma motor running at 36v to start off with
Ordered motor and a 36v Li-po battery from Team Hybrid today..
Going to be in a 26" wheel as it's for road and cycle path use mainly..

Mark says a couple of weeks for delivery as i'm getting him to send the wheel already built..

The bike is an early GT RTS-1..
had it for about 12 years, used to race it..

it's an alloy main frame with a chromoly rear..
and the suspension locks out when on the flat..
not sure how that will work with the motor on there but we will see

 

[fechter]

Welcome aboard!

Lucky there, I can't even find a Puma motor on this side of the pond

That looks like a good frame since there's room for batteries in the frame.

Keep us posted on your progress.

 

[Ypedal]

going for a front or rear motor ?

 

[j3nks]

Going for motor in the rear..
mark says it will have room for a 7 speed cassette..
think i'll bin the front changer and run a single sprocket on the front..

 

[BiGH]

Going for motor in the rear..
mark says it will have room for a 7 speed cassette..
think i'll bin the front changer and run a single sprocket on the front..

sounds like a plan - wait until you set everythig up fully, before rmovign the front cogs. I find i use the front changer more - to help get the bike up hills or to provide top end extra power.

and then u also need a small cog if u have to limp home

 

[j3nks]

fechter..
i know what it's like to be unable to get hold of the goodies you want / need..
a few years back i saw the slipstream bike on the web and thought, i want one of those..
ended up shipping a scott 24v 1hp motor over from the states :?
and since then its been sat in the garage because finding sprockets belts etc just seems impossible this side of the pond..
but one day i'll get round to starting the build

any reason why you hav'nt got Team Hybrid to ship a Puma over to you ?

 

[fechter]

any reason why you hav'nt got Team Hybrid to ship a Puma over to you ?

Right now, my bike project is on the back burner. I'm hoping the price on the Puma will come down, and shipping from GB will certainly put the price out of my range (I'm cheap).

I already have a BMC scooter motor and a gear reduction unit from a Currie that I could use.

 

[j3nks]

Well i've got my bits from Team Hybrid

And i've fitted a set of Rocksox boxxer forks..
makes the bike heavier but they've got 7 inches of travel..
ready for dropping off some big kerbs. haha!!
but they do give the bike a nice attitude..

along with a few others here, i think that if electric bikes did'nt look so geeky :?
then more people might use them..

there is also a pic of the rack i'm going to use to mount the battery..
i've attacked it with the angle grinder..
it's supposed to be good for a 10kg load so we'll see how long it lasts..

 

[deecanio]

nice choice j3nks,

the puma is a good choice and i'm loving the forks
post up some speeds as i have the same kit on 20" wheels so will be good for direct comparison.


cheers


D

 

[Lowell]

Excellent choices on the motor and fork!

Hope to see some videos soon...

 

[Toorbough ULL-Zeveigh]

I'm keen on the Puma as well & will be taking notes on your progress.
Also agree on your excellent choice of platform for electrifying.
Most FS frames eat into the prime real-estate for battery placement & have found few that are ideal for conversion, which yours comes pretty close.
Very clever mounting the shortened beam on the down-tube instead of the seat post, gotta remember that one.

With everyone going dual-crown I'm now having a twinge of regret on recently getting the regular version of the Fox terralogic. It's not just the looks but the added strength that's a must when loading down with batteries. Wish I realized that sooner.

 

[deecanio]

with downhill slightly fading in favour of 4x there are loads of good deals on dual crowns - i got my 04 marzocchi's for £80 from ebay and i love them
i don't think it's that any of us will be getting air but it's great to have all that travel to soak up the bumps and bangs.


cheers


D

 

[oatnet]

Well i've got my bits...

Hmmm.... I am a bit suprised to see radial spoking on a 26" wheel with a (comparatively) small motor... I know it is ok on the giant hubs on my TF, and ok on 20" wheels, but I thought it was a problem on longer spokes. I love the way it looks though, and I'm jealous - still waiting to get mine back from being laced at the LBS!

-JD

 

[Ypedal]

I was just thinking the exact same thing..

I tried radial lace on a 700C last friday and had to go 2 cross instead as the spokes were too long and were out of the nipples ( could have worked but would have had to grind them down to the nipples...

An axle nut behind the torque arm would be nice if possible..

Keep up the good work !

 

[xyster]

Is that a shock absorber in the middle of this pic??? If so, I'm not seeing how it could work -- the triangle looks fixed in place, and there's no leverage at the attachment point.
And it looks like it goes through a hole in the seat tube....weird!

 

[TylerDurden]

The pivot by the BB lets the rear triangle move.

 

[j3nks]

I'll take a close up picture of the suspension set up and post it later..

GT won the world MTB title with this bike years back when suspension first took off..

i think the idea is that when there is tension on the chain,
i.e. pedalling on the flat..
then the rear end is fairly rigid..
No tension, i.e. no pedalling, going downhill..
then the suspension kicks in

By todays downhill standards not a lot of travel..
but for what i need it's perfect..

 

[Toorbough ULL-Zeveigh]

Is that a shock absorber in the middle of this pic??? If so, I'm not seeing how it could work -- the triangle looks fixed in place, and there's no leverage at the attachment point.
And it looks like it goes through a hole in the seat tube....weird!

That's why I think it ideal.
The suspension bits are are efficiently packaged.

 

[xyster]

It also looks as if the rear brake assembly will smack into the back of the seat tube when the suspension compresses even a little. I'm not suggesting it doesn't work, just that it doesn't look like it should work from these pics.

 

[Ypedal]

It's very short travel.. the brakes would be fine..

I like that bike,, alot.. with the added weight of batteries etc and road running , Long soft travel just makes things wobbly/squishy..

Short travel / fully adjustable stiff suspension is best imo.

 

[j3nks]

i think i'm more worried about the back tyre hitting the battery rack..
just fitted a new SCHWALBE "MARATHON PLUS" tyre..
and would hate to take a chunk out of it

 

[j3nks]

Talking of the brakes...
although the puma has mounting for a disc, i'll be leaving the rear with rim brakes..
it's got an hydraulic magura race light, which is superb..
i'll obviously be going with a disc at the front..
still yet to find one though as the rockshox boxxer does'nt use an iso fitting.

 

[Mark_A_W]

i think i'm more worried about the back tyre hitting the battery rack..
just fitted a new SCHWALBE "MARATHON PLUS" tyre..
and would hate to take a chunk out of it

I have that tyre on my front (motor) wheel. So far it's been bullet proof.

It's also so big it gives you more top speed Less torque though..

 

[Lowell]

Talking of the brakes...
although the puma has mounting for a disc, i'll be leaving the rear with rim brakes..
it's got an hydraulic magura race light, which is superb..
i'll obviously be going with a disc at the front..
still yet to find one though as the rockshox boxxer does'nt use an iso fitting.

I ran into the same problem with my Boxxer and had to fabricate my own mount. It looks like the Mono 6ti with a 225mm rotor would be a perfect bolt on though.

 

[j3nks]

a few pics..