BMW K75RT Ultima Restoration

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wollyjumperuk
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BMW K75RT Ultima Restoration: Radiator & Cooling

#61 Post by wollyjumperuk » Tue Nov 20, 2018 10:44 am

Next in line is the cooling system, given the water pump has previously been done, that means the radiator and hoses, so that was popped on the bench...

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...the easiest bit to remove is the stub pipe which fits onto the crank case, so that was removed, the temperature sensor removed and the pipe popped into the vice...

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... which was cleaned up with a wire brush attachment on a drill and the stub pipe masked up before being given a few coats of Plastikote Aluminium Engine Enamel, allowed to dry and the masking removed...

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... and set aside to cure.

So, back to the radiator assembly, the hoses were removed and put to one side, allowing direct access to the fan, which was definitely 'firmly' attached - with 2 seized bolts which were cleaned up with a wire brush and the edges of the heads cleared of corrosion with a pick tool before being treated with penetrating fluid on front and rear...

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... and left to soak for a while, say time enough for a couple of cups of tea!

The bolts were tried again, but no movement was forthcoming. So a little heat was added to gently warm the bolts and the clips they bolt into, gentle because the proximity to the radiator...

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... which, after a fair amount of time, allowed the bolt to be eased out and left me with a loose fan, but it needed some cleaning up after that!

And onto sorting out the state of the radiator parts, starting with the radiator itself, which wasn't in the best of conditions cosmetically...

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... but the cooling surfaces and internal pipe work all looked good and there were no leaks on the ride home.

As nothing was fundamentally wrong, the radiator was cleaned with a rag and WD-40, the blistered and flaking paint removed with the help of a wire brush and a pointy tool, taking care not to damage the internals before being painted with cylinder block paint...

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... and set aside to cure off.

While waiting for that, the thermostat and cap were next up and as these are known to be good, these were cleaned up and the thermostat replaced in the radiator...

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... followed by the cap returning the radiator to one piece.

Next up is the bottom mount which was cleaned up with a wire brush drill attachment and the elbow grease of a good friend, so it was ready for painting.

The mount was treated to layers of Autotek Etch Primer, Halfords Gloss Black Enamel and Halfords Clear Enamel Lacquer and left to cure off.

Meanwhile, attention was turned to the cooling fan, which was tested for function by jumping it across the battery...

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... and it worked faultlessly.

The balance weight was removed, the location marked and the weight was cleaned up before a couple of coats of Hammerite Smooth Silver and set aside to cure.

The fan itself was cleaned up with a rag and WD-40 and the balance weight replaced...

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... meaning the fan is done!

The stub pipe was refitted with the temperature sensor, with the copper washer replaced and the threads smeared with gasket sealant and the unit was fitted with a new o-ring and mounted onto the crankcase so it's ready for the rest of the cooling system.

The radiator assembly was put back together and loosely mounted on it's bottom mounts...

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... as an offering up to make sure everything is where it needs to be (and proving I may need to visit the routing of the front brake fixed pipework, but I'll sort that later).

With that done, all the hoses were pulled together and cleaned up with WD-40 before the hoses on the stub pipe were reconnected...

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... before the radiator could be remounted and the remainder of the hoses reconnected.

Next step was the expansion bottle, which was grabbed from the ever-shrinking parts pile which was cleaned up and mounted back into the frame...

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... which then allowed the air intake ducting to be replaced...

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... finishing both the radiator work and the airbox.

As usual, the system will be commissioned later.

As always, if you'd like further details, please see https://motorcycleprojects.wordpress.com/
Wollyjumperuk
For more on my motorcycle projects, please see https://motorcycleprojects.wordpress.com

mikestrivens
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Re: BMW K75RT Ultima Restoration

#62 Post by mikestrivens » Tue Nov 20, 2018 12:01 pm

nice work
Regards
Mike Strivens

Bikes:
Triumph Tiger 800 XCx, 2015,
used to have Honda VFR800 & Harley Fatboy
Cars:
Mercedes SL500 R129 V8 (1999); Mercedes E320 W124 S6 (1995); Mercedes S600 W140 V12 (1995).

fastbob
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Re: BMW K75RT Ultima Restoration

#63 Post by fastbob » Wed Nov 21, 2018 9:30 pm

A marvellous thread that continues to to delight and inform as it unfolds . This is how its done !

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Speedy23
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Re: BMW K75RT Ultima Restoration

#64 Post by Speedy23 » Wed Nov 21, 2018 9:52 pm

All that notwithstanding , "the opera ain't over 'til the fat lady sings"......

At least we've heard yours singing, fastbob......now, where's that starter button....?
Oh my God, what's happened? I don't know man...I just got here myself!

wollyjumperuk
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BMW K75RT Ultima Restoration: Bodywork Mounts

#65 Post by wollyjumperuk » Sun Dec 09, 2018 8:31 am

As some of the electricals and control cables need to be run through the front bodywork mounting, it seemed reasonable to the mounts done next.

Starting with the front mount, this was pulled together and the rust stripped off, with the remaining paint prepared by roughing up with 600 grit wet & dry paper...

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... before Autotek Etch Primer was applied before coats of Hycote Gloss Black and Halfords Clear Enamel Lacquer and set aside to cure.

Once cured, it was bolted back onto the headstock...

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... allowing the rubber grommets to be refitted ready and cables properly run.

Onto the remaining bodywork mounts, these were grabbed together...

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... and had all surface corrosion and dirt removed with a wire brush drill attachment these were then treated to a good number of coats of Hammerite Smooth Silver...

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... and set aside to cure off.

The mounts were then rebuilt with the original bolts, rubber grommets and mushroom washers before being mounted onto the fixing points on the bike...

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... with one 1 mount requiring the radiator filler cap to be moved to allow it to fit.

To finish the job, the relay mounted on the front bracket was cleaned up, refitted and connected up to the wiring loom.

Onto the next job!

As always, if you'd like further details, please see https://motorcycleprojects.wordpress.com/
Wollyjumperuk
For more on my motorcycle projects, please see https://motorcycleprojects.wordpress.com

wollyjumperuk
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BMW K75RT Ultima Restoration: Handlebar and Controls

#66 Post by wollyjumperuk » Tue Jan 01, 2019 3:42 pm

Getting the bike on and off the lift is a bit of a pain at the moment, so handlebars should help with that.

These were grabbed and popped on the bench and stripped to the bare handlebars...

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... from here the bars were stripped back to bare metal, due to the rust seen on the clutch lever side of the handlebars, before being treated to Autotek Etch Primer, Halfords Gloss Black Enamel and Halfords Clear Enamel Lacquer and allowed to cure.

Once cured off, a length of fairly stiff electrical cable was fed from the centre hole in the handlebars to one end, before the remained was looped around the handlebars and then fed through to the other end...

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.. to allow the cables for the heated grips to be pulled through later on.

This was then mounted onto the top yoke of the bike, adjusted (for now) and torqued down.

With that done onto the controls, which were popped onto the bench in turn and stripped down. The front brake master cylinder was inspected but it will stay in situ, rather than risking damage by stripping it down when I know it works well.

The adjustable parts, such as the front brake light grub screw were measured so that when these are replaced, they can accurately be reset and minor adjustment undertaken from there.

Once stripped down, this left me with 2 piles of bits...

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... things that need cleaning and degreasing and those bits which are in good condition.

The bits that needed cleaning were soaked in Muc-Off Motorcycle Cleaner while the electrical items were tested for function and the screw threads cleaned up by running them through a dye.

With that done, and the parts continuing to soak, onto the electrical switchgrear elements of the handlebar controls...

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... these are known to work, so no further stripping down required. But the controls were grubby, so using a rag with a small amount of WD-40 these were cleaned up. The thing that struck me here was that the markings on the controls were very faded, in no way a problem to function but gives me some research to do to see if these can be replaced.

Once done, the wiring for the controls was fed through the front of the bike and connected up ready for the remainder of the parts, once completed.

Next up was the central handlebar controls which were broken down into it's component parts...

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... and the mount was cleaned up with WD-40 on a rag leaving the next step as the ignition barrel.

On removal the tab retaining this dropped out, it would explain why the barrel was partially push back into the dash, so by using a hot knife this was plastic welded back on to the stump which allowed the barrel to be checked for electrical operation with a multimeter before being refitted into the housing.

Each of the switches on the housing was tested electrically and cleaned before being refitted into the housing.

The hazard light switch was found to have corroded electrical connections and a broken wire on further investigation the internal connections were also corroded...

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... so these were cleaned up with a little sandpaper and electrical contact cleaner before the back of the switch was refitted.

The external connections were de-soldered, the wires stripped back to remove the corrosion and the contacts cleaned up with a wire brush. The wires were then soldered back onto the switch and tested and found to now be operational.

his allowed the central control panel to be rebuilt and bolted back onto the bike...

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... allowing me to move onto the handlebar controls, which required the clutch sensor to be removed with a box spanner...

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... unfortunately this did call for the cable to be cut, but this will be reconnected once everything was done.

With the control parts stripped (yes I gave in and removed the front brake master cylinder), soaked and degreased, the parts that then required painting were stripped using Rustoleum No.1 Green Paint Stripper before these were given coats of Autotek Etch Primer, Halfords Gloss Black Enamel and Halfords Clear Enamel Lacquer...

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...and were allowed to cure off before reassembly commenced with both sets of controls being as built up as possible before even looking at the bike.

While everything was being added to the handlebars, the wires for the heated grips were taped to the wires that had been previously threaded through...

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... allowing the wire to be pulled through to the exit hole in he centre of the handlebars, and the grip fitted to the bar...

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... so the heated grip wiring could be soldered back together and connected up, alongside the wiring for the clutch, brake and sundry dash switches.

Following this, the choke, throttle and clutch lines were run and hooked up, just leaving the flexible front brake line, which was connected to the fixed line and connected up tot he master cylinder.

Things like the clutch adjustment and a decision on if I'm going to take a look at re-marking the handlebar controls will happen with the commissioning and finishing touches respectively.

As always, if you'd like further details, please see https://motorcycleprojects.wordpress.com/
Wollyjumperuk
For more on my motorcycle projects, please see https://motorcycleprojects.wordpress.com

wollyjumperuk
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BMW K75RT Ultima Restoration: Clocks & Horns

#67 Post by wollyjumperuk » Tue Jan 01, 2019 3:51 pm

With the front end taking shape slowly, various work commitments and seeing family slowing work down (but not is a bad way - just in case my wife reads this), it was time to move onto the clocks.

Thankfully I'd kept the clocks in one piece while the bike was disassembled, as I knew these worked and didn't suffer from fogging seen on some K75's, so a straight re-fit, happy times here! With a spring in my step, at the thought of an easy job, I grabbed the clocks and popped them on the bench giving the clear plastic a clean with a dry rag and the black plastic a wipe with a rag just dampened with WD-40, but something didn't look right...

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... it seems when taking this off the bike, I flipped the bracket around and refitted it, so that was quickly rectified (still with a spring in my step!) before the bolt holes were cleared up with a bolt and the tired looking bots replaced with stainless steel upgrades.

But, I went to mount the clocks, something else didn't look right...

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that rubber seal shouldn't look like that. So the back of the clocks were popped off to find that at some point in history the clocks had been apart (probably to replace a bulb), the seal had been allowed to fold over on refitting. This was straightened out and the back screwed back onto the clocks, finally now ready for bolting back onto the bike!

The clocks were offered up, wiring from the handlebar controls directed through the curve (but not the hole) in the bracket, and the electrical connector for the clocks pushed into place...

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... and secured with a small bolt into the back of the housing.

Leaving the handlebar based items pretty much completed...

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... until I change my mind about something anyway!

While I was on a roll, I grabbed the horns...

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... and as these worked well before the bike was disassembled, they were cleaned up, bolted back into place and the wiring reattached...

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... completing 2 jobs in one here.

As always, if you'd like further details, please see https://motorcycleprojects.wordpress.com/
Wollyjumperuk
For more on my motorcycle projects, please see https://motorcycleprojects.wordpress.com

fastbob
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Re: BMW K75RT Ultima Restoration

#68 Post by fastbob » Wed Jan 02, 2019 9:22 pm

Top class work as ever, massive thumb switches !