NC on a diet

[RonniB]

pic of the inside of the carbon tank



You just see the ribs in the knee cutouts, meant to stiffen up that area.
Ronni

[magg]

Is this a track bike only, would like to know what you have changed/removed to get the weight down to 146kg. Is it practical to list them.

[RonniB]

Yes it's a trackbike, so no road gear..

Well, there is a lot, but the overall theme is:
- race bodywork
- New seat and subframe
- magnesium wheel
- Light rearbrake
- Light generator
- Light wireloom
- HRC copy rear axle

Ronni

[Yakama]

Out of interest how much was the HRC axle if you dont mind me asking? Couldnt find it on durbhans site

[RonniB]

I got it from Mruehl34 of here, it was a limited run (one-off) thing he did, I think only 5-10 was/is made. It was around the £700 mark.

The things I listed, was the main components of the rebuild, but of course a lot little thing have been removed, remade and trimmed in the process (which is ongoing). If I were to do it again, I would start out by stripping the bike down in subgroups;
- front end
- frame and front/rear subframe, assorted brackets
- rear end
- engine, carbs and exhaust
- electrics
- Bodywork
Weigh each subgroup and make an estimate of potential weightloss, remove non-essential part and replace fastners with either titanium and alloy depending of stress.
Then look at what lightweight parts where on the market for each subgroup and make budget.
Buy lightweight parts for the subgroups in this order:
- rear end: light chainwheel, brakedisc, caliper, magnesium wheel
- electrics: LiFe battery, dash, wireloom, removing roadgear
- front end: alloy axle, brakediscs, calipers (ISR), carbon mudguard, yokes/stem.
- Bodywork: Thin glassfiber racefairing, RS250 seat
- frame and front/rear subframe, assorted brackets: all steel brackets remade in alloy or carbon, alloy seatsubframe, alloy front subframe(s)
- engine, carbs and exhaust: Tyga exhaust, GSXR generator, remove cam silencers gears, trim down sprocket cover.

Electrics allow you to reposition parts and therefor is more important than other mods. Weight is very much rearwards on a standard NC, so moving and removing weight from the rear is the first you most do, don't think that getting all the weight down low will help, it only makes the bike easy to push around in the garage. Aim for a CoG around 1 o'clock on the clutch cover seen from the right (well, you can't see it from the left).

Ronni