Project Linkins 3LN6 - The Pink Lady

I hooked up the booster battery and cranked it over until the oil light went out, then tried some of the magic starter juice




Dumped the oil & filter, which still looked fresh but given the age it is time to replace. New Ipone semi synthetic and K&N filter. Grateful that this does not have the internal oil filter like the 3LN1 which requires exhaust headers to be removed to change the filter in the sump. Just a simple spin on 303 filter below the front sprocket. (Yamaha used the same idea on the YZF-R6, showing its FZR roots).

I checked the coolant and it seems there was none in there. It seemed to take the full capacity of the cooling system when I filled it. The overflow bottle is currently disconnected and removed so maybe it evaporated away, but the rad cap was in place and seems ok - no damage, no swollen seal and no rust. Perhaps it had been drained. In any case I will dump the coolant after I have the bike up to operating temperature in the future.

I bled the brakes, very crusty and crunchy while bleeding, but I flushed all the gunk through. It's not often you find a bike with an opposed piston rear brake caliper with two bleed screws (one for each side). All sportsbikes these days have a sliding caliper single piston piece of rubbish (even if it has a brembo mark on it). I recall the FZR250 rear brake being very strong and lots of feel, unlike modern sportsbikes.

However, the pistons are sticky so it's likely that it will need a rebuild, so I will probably rebuild the fronts as well. Probably make up some braded lines with the Venhill brake line kit at work.

Serviced the chain and sprockets, which have the correct front sprocket and 428 chain setup. It was all looking very sad until I gave it a good scrub and a lube. Tension was a bit tight, backed it off a little and checked the alignment which was spot on.

I forgot how the FZR's have a 22mm axle nut along with a cute little 19mm locknut The memories come flooding back.

 

Discovered that you can actually get modern tyres in the correct OEM sizes. Pirelli Diablo Rosso Sport. Basically Diablo Rosso 4's but for the small bikes. Unfortunately not a radial tyre but oh well, I'd still wager they are better than sport demons, which are the only other tyre available in both front and rear OEM sizes

• DIABLO™ ROSSO SPORT IS A CROSS-PLY TYRE DEDICATED TO UNDERBONES AND SMALL DISPLACEMENT SPORTS AND TOURING BIKES.
• MAXIMUM GRIP IN ALL CONDITIONS
• TREAD PATTERN DERIVED FROM DIABLO™ SUPERCORSA DESIGN
• LINEAR BEHAVIOUR IN LEAN TRANSITIONS THANKS TO A RACING DERIVED PROFILE
• BRILLIANT WET PERFORMANCE ON LOW-ADHESION SURFACES THANKS INNOVATIVE COMPOUNDS
• WEAR REGULARITY AND ON ROAD DURATION FOR URBAN COMMUTING

https://motorcycletyrewarehouse.com.au/pirelli-diablo-rosso-sport-10080-17-front

https://motorcycletyrewarehouse.com.au/pirelli-diablo-rosso-sport-13070-17-rear

 

Was at work today for a couple of hours so after that I got the FZR on the bench again and inspected the brake calipers. I was able to get the rear piston unstuck by removing the pads, pumping the pistons out one at a time, far enough to expose the dirty areas and clean them up without removing them, compress them back in and pump them out and press back in a couple of times, until the pumped out evenly together and were able to be compressed by hand. So that's one problem sorted.

As for the fronts, thankfully as it hasn't been ridden or moved a lot, there was no fork oil contamination of the brake pads so I can get away without new ones. Cleaned up the discs. However the caliper piston dust seals are starting to squish out so I will need to overhaul the front calipers.

I have placed an order with megazip for fork bushings, clips, dust seals (I will get some Ariete fork oil seals through work), new valve cover gasket and those oil gallery plugs on the cam caps that were discussed in another thread. I would like to replace the oil squirter o-rings and the o-rings that seal the cylinder liners, but my first objective is to get the bike running, roadworthy and registered.

 

Jet housing cap screws ordered.

Diaphragms ordered (ebay chinese ones, Suzuki ones from Mick Hone or Bikebiz are not in stock)

Care package from the @GreyImport on the way

Airbox and litetek kit on the way from @Grasshopper

Will get tyres and fork seals ordered Monday

Few weeks and I should have this bike sorted.

 

They were only $40 AUD delivered so worth a shot. Advertised for Bandit 400, equivalent part number for the Suzuki GSF250 ones. We shall see how they go.

 

Ordered FZR400 fork springs and PD emulator valves for the front, and a rear shock to suit TZR250 3MA. With a change in bushing/sleeve on the top mount (from 40mm to 38mm), any shock sold for a TZR250 3MA is compatible it seems. Opted for a 70-75kg spring instead of 75-90kg based on recommendations from YSS Australia (Suspensions R Us)

 

More little bits of progress.

Assembled the floats and bits from @GreyImport , thank you very much.

One float needle has a stuck spring so needs replacing, I ordered 4 new ones from motorcycle spares warehouse, but they only had 3 in stock and refunded me for one. So I will need to use one old one. They all seem fine except for the stuck one.

The diaphragms have left China and are on the way, should see them soon.

Tyres ordered, nil stock, on the way from the supplier, should see them next week.

My bits from megazip are on the way.

I fitted the coolant expansion bottle, which was difficult because the seat lock is coded differently to the tank and ignition. I had to squeeze it through the side tail fairing. I will have to call our locksmith in to pick it and cut me a key for it.

Started re-assembling the carbs, choke plungers, choke rail etc. Washed the slides and diaphragm caps, all the jets save for one choke jet which is stuck and rounded off in the jet housing are soaking in threebond.

 

I require some assistance.

I am assembling the carbs and have come to the slide needles.

According to our information here, 3LN6/7 should have 5CT7 and 5CT9 needles.

What I have are 5CDL25 (slight taper) and 5CD26 (very little taper)

The 5CDL25 is narrower at the tip, and the 5CD26 is wider.

I don't know which ones are for cylinders 1/4 or 2/3.

Any best guesses or logical reasons for which goes where?

 

Once again searching the forum yields a result

BDST28 throttle butterflys

5cdl25 for 1 and 4 / 5cd25 for 2/3

 

The only difference I have noted, as I've worked on both, is the needle retention is different. 3LN6/7 have the screw in plug in the slide, Zeal has a plastic retainer and additional small spring on the end of the diaphragm spring.

 

Did they not have zeal slides fitted? Mine were round cutaway with double spring and plastic piece. In any case the needles and tubes had no detectable wear on them.

My needle jets are O-2

 

Bits are arriving

 

My solution for removing the fuel tank outlet, fuel tap, fuel pump and fuel lines: DRZ400 vacuum fuel tap. Vacuum will be from one of the inlet manifolds. I plan to just leave it reserve and run out of fuel, then check to see if there is anything left in the tank. If there is, I will re add the fuel pump and leave the tap on prime. It still would eliminate extra fuel lines.

 

Diaphragms arrived and are a perfect fit. Test assembled one and checked it against the slide with the spring fitted and cap held down - no problems.

Just waiting on airbox and litetek kit from @Grasshopper and I wil have this running.

Expecting tyres to arrive this week (after two delays) and next week I should have all the suspension bits here.