New build - Old bike GT LTS

[Wurly]

I thought i might start a thread for my latest project. (I think i am going to need plenty of advice for this one).
I have been looking for a suitable full suspension bike as a candidate for the next project. Requirements were, cheap, good condition, steel frame and local to me for collection. There are many aluminium framed bikes to choose from and i quite liked the look of a D/H style of bike, but I am 50+ years old……
So setting my sights much lower i ended up with this. Much more my style
A 1998(ish) full suspension GT-LTS one owner never raced and little use for a princely sum of £114 (and it was only 30mile to collect it).




The 19" frame is just about the right size for me and there is a nice big triangle to fit all the batteries and electrical stuff.

After a long wait my BPM code 10 hub arrived from Evassemble just after christmas. The hub was held up in ‘customs and excise’ and i had to pay a £30 fee before the couriers would deliver it.
Once paid, it arrived next day.



I had bought a new 36 hole MTB rim in readiness some while ago, so it was straight onto the pc and get some spokes ordered.
While waiting for the spokes i decided to fit the hub to the bike and see how it fits.
The drop outs on the rear frame were very shallow in depth, so i had to file them deeper for safety.





The flats on the spindle are now firmly located within the slot. I could have filed it deeper but i already planned to have torque straps.

[Wurly]

The supplied torque washers were a nice fit and substantially stronger than the flat pressed steel washer normally supplied with the smaller 250W bafangs. Being 4 mm thick as well, I can make good use of these.



I wasn't looking forward to filing out a perfect slot in my torque arms. This seemed like the easiest and strongest option. Drill a 23mm hole in some flat steel and weld the torque washer in the correct position.





I wasn't sure if chinese metal was going to weld ok but i need not have worried.

[Wurly]

I added a welded captive nut to the inside of the frame.
Torque arms completed.

On to the next job.......post some more update soon.

[Wurly]

Lacing the wheel....

One thing was bothering me. The spoke holes on the BPM measured 3.1mm and i'm going to fit 2 mm spokes.....mmmmm. How is that going to work out? the holes seem too big to me. There is a deep countersink to them also.
I decided to fit little 2mm washers to the spokes. I simply dished each one using a centre punch before sliding the washers onto the spokes.
I am not sure if it was really necessary, but in doing so makes me feel happier that the spokes are not going to work there way through the hub.



So....armed with my 'The Bicycle Wheel' 3rd edition by Jobst Brandt, i set about lacing the rim to the hub.
I think i have laced about 7 wheels now, so it's getting easier each time. But i may have messed up with this one...



Here is the complete wheel nice and true.
I have pretensioned the spoke as you are supposed to do and re-trued the wheel, but i am a bit unhappy with the angle of the spokes at the nipple. There is a fairly sharp pull. I thought about this and decided to bend a slight angle near the nipple end but further up the spoke away from the thread. I figured this would be preferable to the spoke trying bend on the top of the thread (weakest part).



I now know.....i should have used a 1x cross pattern rather than 2X. Live and learn. If it causes problems i'll simply relace it with shorter spokes .

I discovered the supplier cut the thread instead of rolling it. I retensioned the spokes once again and it seems fine. Time will tell and i will be checking no fear!!!

More up dates soon.......i hope you are finding this interesting?
Any comments good or bad welcomed

[Idontwanttopedal]

Looking good

[veloman]

Nice job on the torque arms. Try to anchor one more bolt on them if you can to prevent rotating.

[Wurly]

Thanks IDWTP i've been watching your build also...wicked

Veloman, do you think a second one is better? Yes i thought so too, but i miscalculated where to drill the second hole, what i'll do is weld up the hole and redrill another (in the right place).

I'm currently working on the chainset/freewheel gearing, hopefully the chainset mods will be finished later today if the parts arrive.

[veloman]

Just try to make another hole to bolt through, as far as reasonably possible from the other bolt, going into a good section of the dropout.

That would prevent any rotation if the axle nuts ever came loose.

[Wurly]

I knew the MTB chainset would have to be changed or modified, so i started looking out for a replacement. I couldn't believe how much new ones costs......i want to save my cash for batteries!!!!
So I bought a single 53t chainwheel from ebay £2.99 + postage came to around £6....with a homemade adapter plate i reckon i can make it work.
I found a circular plate of aluminium (or alooominum) in the garage just about the right size. I turned out the centre with a lathe and marked out the BCD and drilled the relevent holes. I drilled them slightly undersized and filed out the last bit for a perfect fit.




I also ordered some chainset bolts and they turned up today. Nice red anodised ones. Not sure what these get used on...fixed wheel bikes i guess.
Trouble is they are a bit too short, and they seem very weak. I might have to get some different ones.....steel ones. I thought about polishing the adapter plate, but what the hell it'll get covered in grime before too long.

This is how it looks now.....just waiting for an 11T 7speed freewheel.

[Lenk42602]

wurly,

nice! if your bushings need replaced, there is one place in the world that I know of that sells NOS replacements for the LTS series of frames..

http://www.benscycle.net/index.php?main ... f3fb1f2826

good luck with the build. that platform was where the magic really began for me!

Len

[Wurly]

Thanks Len
I have taken all the suspension fittings apart to check wear and they all seem ok. tbh i don't reckon the bike had much use before i bought it.

I have made a bit more progress. The 7 speed freewheel turned up earlier this week, so i fitted it to the hub for a trial fit. The thread was nice and clear and it slid on no problems, but, do you think i could get the thing off again?? no way.
I had to buy a freewheel removing tool. Not a bad idea to have one in my toolbox anyway. While waiting for that to arrive i realised the freewheel extends way past where my frame sat against the spindle. Adding some temporary spacers solved that issue.


An improvement i want to make with regards the freewheel frame clearance issue is a spacer that can take the load of the bike insead of relying on the threaded part of the spindle, this of course has a hole drilled down the middle and leaves the whole assembly incredibly weak.



Now i discover the rim is no longer central to the frame. It needed moving about 4-5mm. I had to dish the wheel, which was a shame because i had it running nice and true. Oh well, it gets easier each time i do this.



With that problem fixed, it was time to see if everything lined up ok. I added 10 links to my chain and to my suprise the chains and freewheel worked perfectly. I couldn't resist running the hub, so with my bike turned upside down i quickly ran the phase wires from my other daily ebike to see how the gearing match to the hub speed. The motor runs at 25mph no load speed, although i didn't time the cadence, pedal speed is 'comfortable' and i was one gear up from the 11t. When i decide what batteries and voltage i am going fto fit, i know the chainring and freewheel is going to be matched ok.



Today i got a chance to ride it for the first time. With every available battery in my possession, i 'cobbled' them all togther to give me 36V 15ah [with diodes :0) ] They are 36Volt 5Ah pings batteries.





I am used to low powered hubs and controlling the power used to get maximum range with light assistance.
This is new to me. The BPM is very power hungry compared to what i am used to. My controller was hitting current limit. It did improve as things warmed up. I went for a 5 mile ride and couldn't keep the current much below 15A. My turnigy meter showed a peak of 22A although i am sure the controller was cutting out earlier to begin with. I used 2.2Ah, 107wh and speed was around 21mph. The bike isn't setup to my liking yet and i obviously have the wrong electrics, the crappy MTB tyres were dire and i nearly came off into a tight corner....... (It was an experimental ride just to see what improvemants i need to make). I have already ordered some schwalbe city jets so that should improve rolling resistance. Incidently, i can achieve 24mph on my 260rpm tongxin marin commuter bike with way less power consumption, so there is plenty of scope for improvement on this bike.

Now i have to decide about controller/batteries/voltage etc etc

[ohzee]

Looking good you seem very capable.

[Wurly]

Thanks

Yeah! capable of messing things up

Actually, i'm struggleing to come up with battery ideas. I know the BPM isn't anywhere near the high power bikes on this forum. I'm not sure what C rate batteries are going to be needed with this setup. I want 20mile range and be able to carry my charger(s) with me to charge where ever i go, so i guess, Lipo is probably not the ideal option. I was thinking headway cells from BMS battery. It seems a cost effective way of getting a decent pack that i can put together myself. I love the ping batteries. One is nearly 3 years old and still performing well on one of our ebikes, but i need more volts. I need to move up. Which is one reason for posting my project on here, i need advice.

[Scottyf]

Only just got round to looking at your build Mel.
Very good and should be alot of fun and very comfy with the full suspension.

Get it on 44.4v and let it go 25mph ish and it will be alot more fun. Try not to destroy the bpm like i've done with wet weather Winter riding.

Far nicer build than mine which is more of a bodge it job.

[Wurly]

Hi
Time to update my build thread. The bike is 'on the road', not finished (are they ever?) but it's in a usable state.
So let me back track.
I was thinking about building a pack out of headway cells, but this ping battery was for sale in the classified section. Not a bad price and it saved me shipping, duty and taxes. Not my first choice of battery, but an instant solution.
It's a 48V 15 Ah, which should be good for 35A peaks thereabouts and should give me (by my calculations) a 25mile range. I want the bike to be able to cruise and just over 20mph and have plenty of higher speed should i ever require it. Range/time was actually a more important feature than absolute power.

It's a bulky thing.










I like the downtube fitment in the last photo but i want to be able to remove the battery easily and the top tube will be in the way. I'm going to fit the battery as the first photo.
My intensions are to make a slide in mounting bracket and house the battery and BMS into a metal sleeve which can be removed from a bracket fitted to the bike. I don't mind a bit of fabrication so i borrowed a sheet metal folder and made up this box.
The BMS is fitted to a thin piece of plywood and the cover is made from clear acrylic plastic and a bit of kapton sheeting for more insulation.

The charging socket and anderson power pole are fitted to the cover.





Next thing to make was the bracket. Well....it's more of a sliding shelf really. Here are the bits and peices....



And it all goes together like this.





I welded in a couple of aircraft overcentre fittings i had 'aquired' i think it's a nice touch. I just need to carry a 12 sided 3/8" AF spanner with my toolkit to remove the battery. It's not going to be the easiest thing to steal unless you know how it all comes apart

[neptronix]

This the perfect dual suspension bike that will fit a falconEV bag. I need to find me one of these !!

Good build so far, i like the torque plates.

[whereswally606]

nice build wurly, love the frame and your custom torque plates, was looking at a GT like yours on eaby this week, shot up from 10 pounds to 165 in one bid, shame, it did have lots of nice after market extras though. Probo have enough bikes to be getting on with though since im on my 3 build now.

keep up the documentation its good to see the progress, like the shelf idea too

[Wurly]

The first ride was exciting Using a KU123 controller a freshly charged battery i couldn't believe how fast it was. The motor seemed to engage with a thud and i was up to 28mph before i knew it. A quick glance down at the power meter and i saw a reading of 50A.Jeez.
I connected the 2 white wires to tame it down a bit, with careful twisting of the throttle i had more control. Looking at the wiring for the controller once more i realised there is a 'speed switch' setting. So i also joined the black and green on the spare 3 pin socket, this reduces power even more. Now i have two switches on the handlebars. I couldn't get the KU123 controller to fit my triangle bag so i replaced it with a KU93. All is good.....

I had a family weekend away at Exmoor and few weeks ago. Great place to try out the bike. While the others were out walking, i was riding
If you've ever heard of Porlock hill then you know it's one of the steepest climbs around this part of England. Considering this is a code10 wind and really mean't for top speed, the bike pulled me up with no trouble. I used 3.5Ahs from the bottom to the top of the hill. Came back down the toll road. The best fun i've had on 2 wheels for a long time, nearly got my knee down a few times.

[Wurly]

Yep, i spent a long time looking for the suitable victim. Try to get one thats a steel frame (including the rear frame). £165 is ok if there are nice parts fitted.
I am really pleased with this bike. I have never had full suspension before, it rides lovely.
I have to upgrade the brakes....i mean, i really have to. Coming down the hill after this climb the brakes heated up big time. The rim and the tyre was hot and the brakes were squealing like hell.
The front forks have the brackets for a disc brake, but the rear don't. I will have to fabricate a bracket and weld it to the rear frame. I think there might be disc clearance issues too.
Work in progress...........

[Wurly]

My brackets and battery box were starting to go rusty (like everything does in England), so a coupleof weeks ago i decided to paint everything up. I had a spare BPM that needed a shot of paint, so everything was masked up.

Damn i wished i did this at the very start before i laced the wheel. It's really fiddly masking up every spoke



On goes the etch.........

[Wurly]

2 pack shiney black







Assemble the battery box for the last time, i added some black plasic with a tiny window to view the BMS led's


Thats much better.

With the yellow frame against the black it makes the bike is a bit more stealthy. Time well spent.

Improvements needed are the brakes, i'd like to wire in a current limiter, dcdc converter for hard wired lights some method of carrying stuff.
A front rack probably.
Having ridden the bike recently, it's turned better than i thought it would. Not ridden it any distance so far, but i'm sure it can take me at least 25miles at just over 20mph average for any terrain. I use the bike for commuting and will ride it to see my elderly father instead of taking the car each time.

Approximate costs

£114 for the bike
£160 for the BPM (got stung for duty and customs)
£25 rim and spokes
£23 for the controller
£10 throttle
£25 turnigy meter.
£330 Ping battery
£25 wire/connectors and paint
£22 for Schwalbe tyres
£5 for 53T sprocket
£5 chain
£25 screw on freewheel.
£769 all in (give or take fifty quid)
A bit more than i expected having listed everything, but not bad value, and it's been fun nailing it all together.

[M1k3]

My parents live just inland from Porlock ,that is a very impressive climb respect indeed ,lovely build by the way,have you done a build log on the other vehicles in your garage ?

[Wurly]

Porlock isn't very far from me at all, about 50 miles if that, it's a really nice area. I should spend more time there. We were renting a farm house. It's brilliant for electric bikes. I know some cyclists can ride up Porlock but it's real hard work, i don't think i could have even in my youger days.
I have build up photos of both cars, not for here though.
If you look at my photobucket link from the bike photos you'll find more.

[motomech]

Since most of the stopping power comes from the front brake anyhow, why don't you try going with the front disc. only before welding on the frame. It might be enough.
What are those cars in the backround?

[Wurly]

Not much to add, except i put some disc brakes to aid slowing down.
They are Avid BB7 160mm. I bought some brand new wheels and laced up the rear hub once again so front and rear wheels match, this time using 13G spokes in a x1 pattern.
Loads of work, but much improvement. The front discs might need changing for larger diameter one day.
There wasn't a bracket on the rear frame so i fabricated one and welded it in place.
I also treated the bike to a comfy new seat.

Bike is running really well and the BPM motor is getting quieter the more miles i put on it.
No issues with the Ping battery either.

(Not a very good photo)