Wiring for temperature gauge.

It's very useful to photograph every step of the strip-down, for reference during re-assembly. You'd be surprised how much detail you can glean from a series of photos you took a few weeks ago, and at how much you can forget in that time. Referring back to the position before dismantling began makes the re-build much easier.

While grubby on the outside, I was surprised to find the headstock bearings inside were clean. A first inspection suggests they don't need replacing but experience tells me it's not until the bearings are thoroughly de-greased that it's possible to spot tell-tale pitting and traces of wear.

Currently stripping down the brake calipers. Out of eight pistons, seven were stuck solid. Astonishing the brakes even functioned. Probably because the discs had "adapted", which explains why they measured 3.4mm.



As of lunchtime, three pistons are moving. In the absence of a high pressure line, the "bicycle pump" technique is working fine. Clamp the pump to the bleed nipple, slacken the nipple's seal bolt, and administer 40-140 ft. lbs.. Be sure to place some wood between the pistons to absorb any shock as they jump forwards.



Do NOT forgot the pump isn't connected to your push bike, and disconnect the pump without tightening, and thereby shutting off, the bleed nipple. A brake fluid fountain awaits anyone who forgets...

To remove the last two stuck pistons the brake calipers are enjoying a Coca-Cola bath.



I haven't tried the Coke bath before, so it'll be fun to see how they turn out. I'm told, twenty-four hours ought to do it.

blow torch is your friend,

i heated mine up and then used knocked a socket in and turned them out,

if your not fussed about knackering the pistons drill a small dent into the edge of the piston, and then using a hole punch lever them out

The need to pay for new brake discs - Abrmoto's Yamakatas - means I'm trying the least destructive piston removal methods first! If I had to buy new pistons, some secondhand SP2 calipers from the US might be better value. Thankfully, the pistons extracted so far all look fine. That said, the time taken to remove seized pistons does make one think about retro-fitting non-OEM stainless steel pistons.


Yamakata NC30 brake discs

For generally humid Thailand, esp. the rainy season, stainless brake discs make sense, too. The question is, how will they stand up to the local mountain descents? At least the EBC HH rated sintered pads that arrived today look substantial. With a full overhaul and a new set of shiny Goodridge SS brake lines & fittings, carefully bled, these brakes ought to be pretty good. I hope!

Phoned the powder-coater to check he was in, struggled around the Chiang Mai Flower Festival carnival, numerous blocked roads, police roadblocks, & some inspired "one-way" systems, to find the work hadn't been done quite yet. No worries, got a price for coating the fork lowers, which I'll drop off next week.

But that was after I had been to the aluminum fabricator. They had finished the screen frame, and the Al. bars. When I track down some digital scales (how can these be hard to find in the Golden Triangle?), I'll post some weights. At a guess I'd say both parts were at least 50% lighter than the original.

Dropped off a cardboard mock-up of a lightweight aluminum dashboard and front fairing strut. The fab. boss (sorry!) said he would order in some 3mm box section aluminum, and I'll head over next weekend to confirm the design. I left them with my cardboard model, and an order for one 2mm Al. dash face plate, to size and cut-outs for Tacho & Temp, and a 3mm Al. back plate, which will eventually be bolted to the front fairing strut via, er... That bit I need to work out.

Without the speedo there's plenty of room to mount the temperature gauge and "idiot" lights in a more visible position. The lights are LED's, with nifty metal bezels, in the appropriate colours. Though, I'm not sure if the headlight "full beam" LED will be too bright at night. If it is, I'll bung in another resistor to lower the current. For the standard LED's, Ohm's Law R=V/I => the resistance should be the voltage divided by the current -> 12v & 10mA (at a guess) => 10V/0.01 = 1000 Ohms (assumes the voltage across the resistor is likely 12V - 2V = 10V).

A 1000 Ohm resistor will be brown, black, red, gold (or silver or whatever, the last band is the tolerance, and LED's are tolerant so it doesn't really matter). Or, 1000 Ohms in a 5 band resistor will be Brown, Black, Black, Brown, and then Gold or whatever. (Oh dear, can you tell I built my own valve based hi-fi...)

Left the Boss with the horrid, heavy NC30 kickstand. Wish I could find a CNC machine and some 7000 series aluminum to build a better bracket, but at least the leg will be in over-size aluminum, with a large "foot". I'm hoping the foot will reduce the risk of the bike toppling over when parked on hot tarmac, or soft grass.

Meanwhile, photos of the alloy parts to go here... and here... tomorrow.

Picked up some powder-coated parts today.



I'm very happy with the finish. The gloss parts came out an almost liquid black.

Dropped off the fork lowers for their powder-coat, and the nice lady from Honda Chiang Mai gave me a new Honda emblem for the fork yoke when I collected a handful of parts that had been on special order.

A delivery from David Silvers, and mice in the NC30 exhaust can! More tomorrow. With photos. I know, I keep saying that...

Cool thread....we want mice!