ESE's works engine tuner

[katinas]

Nice!
Thank you.
I managed to get my Tz/Tzr project to 78kg so far.(no front fairing)
I have been obsessed this winter with trying to shave weight off of everything.
I´m aiming at 75kg´s(it´s becoming hard now)
Already bought every bolt and nut in titanium and aluminum
Exchanged all steel available on chassis to aluminum.
Lighter wheels and tires
Cut away unused brackets etc etc.

78kg´s is a success so far =)

78 kg weight with 250 cc two cylinder, impressive, it's completely on the edge.
With such a low weight, wheels/ tires/ brake discs, must be extra light, otherwise, softer springs in harmony with 78 kg will not be able to work with normal 250 wheels and tyres. Or if you leave the standard springs, the suspension will be very hard. The closest would be 125/moto3 wheels and tires.
Very light carbon brake discs can be made inexpensively from F1 brake discs from ebay (I bought few discs with pads for £50 per disc). After cutting one disc in half, you get two discs with a maximum thickness of 9 mm. Only needed to make the inner part of the brake disc from magnesium. Four lightweight carbon brake pads can be made from one F1 pad.

[katinas]

https://www.ebay.co.uk/itm/374339219849

[wobbly]

After months of work on the factory Vortex KZ engine I have been tuning its all ready to run.
But , suddenly my SportsDevices SP1 Inertia dyno control box has a Coms issue and wont talk to the laptop.
Anyone on here using one , I only need it for a day to urgently to do a couple of runs , and can load my own dyno config file.
Any help very gratefully accepted.

[husaberg]

It took me a bit of looking to figure out they bead rolled the bracket to go over belly weld.

re the last pic knowing HRC i suggest the bracket might be hydroformed pressed rather than hand shaped.

[SwePatrick]

78 kg weight with 250 cc two cylinder, impressive, it's completely on the edge.
With such a low weight, wheels/ tires/ brake discs, must be extra light, otherwise, softer springs in harmony with 78 kg will not be able to work with normal 250 wheels and tyres. Or if you leave the standard springs, the suspension will be very hard. The closest would be 125/moto3 wheels and tires.
Very light carbon brake discs can be made inexpensively from F1 brake discs from ebay (I bought few discs with pads for £50 per disc). After cutting one disc in half, you get two discs with a maximum thickness of 9 mm. Only needed to make the inner part of the brake disc from magnesium. Four lightweight carbon brake pads can be made from one F1 pad.

Yes, i´ve been working hard.
Every little thing that i have bolted onto the bike needed to go through my lightening process, machine? lighter material? etc etc.
the handlebars for an example is carbon fibre, all fasteners thoughout the whole bike is either titanium or aliminium
All steel products exchenged for aluminium, i even have built my own rear shock.
the lower part of my upside down fork (dunno the word, normally the chromed steel tubes) are now aluminium.
Every little unused bracket is cut away on the frame and engine.
Engine has no kickstarter anymore, all gears to that are gone.
Front rim is an Magnesium 1.5" wide 17" rim.
Rear rim is an lightened frontrim from RGV250
Tires are lightweight ones, front is a tire that needs tube, but i run tubeless, rear is a PMT rain tire(soft rubber)
The fairing, (tankdummy and rear set) is one layer carbon fibre with some reinforcement on specified places.
But as i said, i doesn´t use a front fairing.
I even bought a new fueltank(1 litle) it´s weight is only 115g, the old one 1.2kg´s
The wheel axles and swingaxles are ofcourse titanium.
Made a new swing in aluminium.

And remember, it´s a 201m racebike, not a trackbike that is running lap after lap after lap.

Picture during process of making own rear shock:

[Grumph]

Years back I had a 750 Kawasaki left in the shop after a visiting rider fell off and went home to heal. Looking it over it had titanium fasteners all over it and obviously a lot of money had been spent. When the rider returned a couple of weeks later i commented on the Ti bolts and showed him the equivalent size nylon fasteners. He'd never seen those and was surprised first at how light they were - and then by how cheap they were.
Absolutely fine to use for non - structural purposes.
John Britten went about it differently. Everything you'd expect to use 6mm fasteners used 5mm and there were similar size reductions all over the bike. If it had to be large OD, it was usually hollow.

More than one way to cut weight.

[husaberg]

Years back I had a 750 Kawasaki left in the shop after a visiting rider fell off and went home to heal. Looking it over it had titanium fasteners all over it and obviously a lot of money had been spent. When the rider returned a couple of weeks later i commented on the Ti bolts and showed him the equivalent size nylon fasteners. He'd never seen those and was surprised first at how light they were - and then by how cheap they were.
Absolutely fine to use for non - structural purposes.
John Britten went about it differently. Everything you'd expect to use 6mm fasteners used 5mm and there were similar size reductions all over the bike. If it had to be large OD, it was usually hollow.

More than one way to cut weight.

A modern 4t MX bike is a great example of fastener minimalization. if they went to the same efforts on the 2ts they would be 85-90KG's
One detail people often miss with the Britten was a aluminum front and rear hollow axles. It was a scaffold tube part about 1 7/8 inch 6061 series. 4.47mm thickness 48mm od
1.6KG/meter.

To me Johns alloy axels rate higher than Poxy 12mm TZr250 and 15mm FZR axels.

Nowdays they even do front axels 22mm with "special bearing" on the YZ'fs and a few others.

69/22 2RS,
which is 22mm x 39mm x 9mm.
Rears, are 6905 2RS,
25mm x 42mm x 9mm


Kevin Cameron did a great one on the TR750 where the young engineers decided they could save some weight by adding dollars.

edit
and no i am not saying that's what's going on in the posts above i utterly love the cf discs and engineered lightness

[SwePatrick]

This is a deep deep wormhole that one can make oneself not beeing able to get out of =)

[husaberg]

Sketchy's rear disk and Caliper is off a MTB

[SwePatrick]

Sketchy's rear disk and Caliper is off a MTB

Guess what i´ve got already?
And also a bonus pic of new fork parts, not fully done yet, but as is ~600g lighter together witn the new 'shaft' that connects the both it´s over 1kg weight saving.

[husaberg]

Guess what i´ve got already?
And also a bonus pic of new fork parts, not fully done yet, but as is ~600g lighter together witn the new 'shaft' that connects the both it´s over 1kg weight saving.

Now does that disk really need to be iron.....
ktm50's have really neat calipers and master cylinders made by formula who made mtb brakes compete with plastic pistons and are nippleless.

for scale the disc is 140mm

[pete376403]

Kawasaki had plasma sprayed aluminium disks on their racebikes years ago. (pre carbon age) No idea how well they worked. Bro-in-law made an aluminium rear disk for one of Bruce Ansteys TZ250 as it only had to work for scrutineering, he never used the rear during races.

[wobbly]

Rotating mass ( angular inertia ) has a huge effect well beyond that of simply reducing the weight of everything in sight,
I have done a back to back with Mag wheels Vs BST carbons on a Superlight, the data showed the bike gained 6 bike lengths on the main straight at Hampton , and
then promptly broke the lap record.

And when testing the BSL500 V3 at Sepang we tried a 12,000 GBP carbon /carbon/Ti dry clutch assembly from AP.
When accelerating side by side out of the last left hander onto the main straight , the AP bike pulled a bike length on the standard one for each of the next 4 gear changes.
That was very cool , but it soon became obvious that none of the 3 people who tried could do a decent start , no matter what technique was used.
The thing either promptly stalled , or threw a huge wheelie . Nothing in between was possible. Luckily this could not break Mr Buckleys bank account or enthusiasm.

When we did a demo against the Britten at a race day we ran out of Carbon pads , so had to fit the front steels usually used in the wet.
It still did over 300Km/H but was 2 secs slower overall - still smoked Johns bike , with 155Hp and 115Kgs as you would expect.

[Grumph]

I've seen reports of hillclimb cars using the carbon/carbon clutches doing a clutch warmup by parking against a barrier and revving against a lightly loaded clutch.
Better feel apparently once hot. Still with little or no measurable wear after a season's use.
Bill B always appeared to have deep pockets but short arms at the pub when he came down here in his speedway sidecar days. That was a tough, hard drinking crowd of mad characters on the chairs.

[F5 Dave]

Kawasaki had plasma sprayed aluminium disks on their racebikes years ago. (pre carbon age) No idea how well they worked. Bro-in-law made an aluminium rear disk for one of Bruce Ansteys TZ250 as it only had to work for scrutineering, he never used the rear during races.

Ha, was going to use his bike as an example. Rear brake lever was made from Perspex.

Plenty of ally discs in Buckets. Use organic pads.