Author Topic: New XR75 K1 1974 Project  (Read 1868 times)

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Offline alexbrown64

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Re: New XR75 K1 1974 Project
« Reply #15 on: September 05, 2017, 09:03:40 PM »
Thanks Big Scotty.  I forgot how much fun they are. Went up my road today with a big smile on my face. I am just putting another big order together with re-mx which should be the final order to get a decent rebuild.  Hope your XR80 is up and running well.  re-mx sells a bunch of parts for pretty good prices and really helps with getting the old girls up and running.

I have this retro jersey in a small size coming for the lad to match the bike..



Cheers


Offline alexbrown64

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Re: New XR75 K1 1974 Project
« Reply #16 on: October 02, 2017, 12:00:49 AM »
Got stuck into the little XR.
As usual, the more you look, the more you find. The major problems are:

1.) shift shaft, which is stripped and had the shift lever welded on. 
2.) The footpeg bar mount. This 4 bolt mount attaches to the engine.  It looks like a pretzel and has numerous cocky shit welds and patches all over it.
3.) Pipe. Completely smashed and has numerous cracks.
4.) Rear brake lever. This was bent beyond recognition.
5.) Broken alloy footpeg mount on the engine case.

The rest of the stuff is just rust, wear, abuse and age. 
I pulled the bike apart and bagged everything up.  As this rebuild is just a tidy up to have her ready for a bit of fun, i am not going to far.
I straightened up the brake arm and got it ready for the powdercoaters. Had to make sure it cleared the pipe and was functional. 
I cleaned up, ground and rewelded the footpeg bar mount. Also filed the pegs.  These are all going to the powder coaters.
The pipe has been replaced with a  power pipe.
I have removed the clutch cover ready for polishing, and this is where i will go through to replace the shift shaft.
The alloy footpeg mount which is part of the cases will be repaired with the rods i purchased.

I used an abrasive flapper wheel and then a cloth wheel with white polishing bar on some of the alloy covers. I am having great results and will post pics soon of the before and after results.

Pic below of munted brake lever...



Brake lever repaired and ready for powdercoaters..



The rest of the bike is bent, corroded, worn, missing, forked etc... but great fun to rebuild.  And she does run!!



Cheers


Offline Krikey

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Re: New XR75 K1 1974 Project
« Reply #17 on: October 02, 2017, 08:47:20 PM »
I'ma bit inspired Alex. I've got a couple of 74 K1s in the shed in boxes.  I think I'll have to start rebuilding at least one of them soon

Offline alexbrown64

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Re: New XR75 K1 1974 Project
« Reply #18 on: October 02, 2017, 10:47:27 PM »
Lucky you Krikey.  I think the K1 was the best looking model with its yellow graphics over the metallic grey.
Hope your two are in better nick than mine. Must admit, they are really rewarding to work on.

I had a go at removing all the old paint from the frame, swingarm, plates etc.. bought this biodegradable paint stripper from Bunnings.  Might as well of rubbed banana on it.  It was useless.  I could of rubbed it in my eyes and i would of been ok.  Had to go back and get the real stuff.  This had the paint bubbling off and i used the pressure washer to blast it back to bare metal.

Not sure which way to go with the black paint.  I bought 2k black and clear coat, but i am leaning towards taking everything to the powder coaters as i want to get the pegs, peg mounts, bash plate etc.. done in powder coat and i also have my YZ125G frame to take up and get done.

 


Offline Big Scotty

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Re: New XR75 K1 1974 Project
« Reply #19 on: October 03, 2017, 03:09:45 PM »
Gday
Got my parts from re mx,new seat foam and cover,new fork legs,been busy out in the shed and got it all back together,double checked everything then time for a test ride,do you think the basted will start,I have had it running on the stand,first kick every time,now it's back on its wheels it won't go,time to walk away.bloody hondas????????????
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Offline alexbrown64

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Re: New XR75 K1 1974 Project
« Reply #20 on: October 03, 2017, 04:36:57 PM »
Great to hear Big Scotty that you got the XR fixed and ready to rock. Strange that it wont start.  Best to walk away and have a think about it.  Cant be much.  Been sitting a long time and may have pulled a bit of crud through from tank or airbox and stuck in the minute jets.
Once i put my new carb and coil on, my little XR  burst into life easy..

Post up some pics once you get her running..

Cheers,


Offline Big Scotty

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Re: New XR75 K1 1974 Project
« Reply #21 on: October 03, 2017, 04:57:28 PM »
Got it going,lots of fuel leaking out of the carb and I think some is running into the engine as well,did you buy your new carb from re mx and how was the jetting,I think either a rebuild or new carb
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Offline Mick D

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Re: New XR75 K1 1974 Project
« Reply #22 on: October 03, 2017, 09:51:21 PM »
Got it going,lots of fuel leaking out of the carb and I think some is running into the engine as well,did you buy your new carb from re mx and how was the jetting,I think either a rebuild or new carb

Nice,

I think the Rubber tip on the float needles go dry and hard in the  absence of fuel and use.

Anyhow that is what I found with the XR500 when prepping for the Bulahdelah Vinduro.
I always undo the drain screws on the carbys when stood up.
It had been sitting unused for a couple of years.

Kept tapping the bowl with the plastic butt of a screw-driver. Would sort of nearly stop leaking,,,
But eventually did after a few days soaking with fuel again,,,,

Moral of my story for me is = start them and use them more often.
« Last Edit: October 03, 2017, 09:53:42 PM by Mick D »
"light weight, and it works great"  :)

Offline alexbrown64

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Re: New XR75 K1 1974 Project
« Reply #23 on: October 03, 2017, 10:04:54 PM »
Got the carby from Re-mx, as everything they sell seems to fit and work well. It fitted straight up, but i did have to bend the choke lever away from the frame. 

Didnt touch the jetting.  It started straight up, idled perfectly and i took it for a blast around the park and it ran perfectly, even with the new power pipe.  No burps or backfiring. And this bike has been abused, so im sure yours will be fine.
 
I did make sure the ignition system was good, by replacing the coil, condenser and putting new points in and setting the gap.
I also adjusted the valves.
I cleaned the tank out.

So far i have bought a set of rear shocks, carb, rear mudguard, points, coil, condenser and a few other items from Re-mx.
I have also bought a huge heap of OEM nuts, bolts, grommets etc from Partzilla.
I got some of my decals from Fastguystuff and the others from re-mx and partzilla.

The K1 is now ready for the powdercoaters.  I am sending the frame, airbox, pegs, peg mount, bash plate, seat base and a few other nick nacks all to be done in gloss black. I have stripped the paint and buffed all the parts. The swingarm i am doing myself in 2k gloss black. This is so i dont have to get the rubber bushes removed and replaced.  I did it once on a similar swingarm and it took the shop about an hour and a 10 tonne press and new bushes.

As usual, there is more work involved when you get pulling them apart.  I now want to strip the wheels, buff the hubs and replace the spokes.  This is still only a basic rebuild, but i want it to run and look reasonably smart.

I have also been playing around with various techniques to buff the engine.  Its not perfect and not oem, but it looks respectable and gives the bike a bling factor. So, i will have the rubber gray paint, oem style decals, white front oem plate etc.. but will have polished engine covers and hubs.

Bits i gave a quick buff and polish today... one of the brake plates hasnt been done yet.  If you have a look at previous pics, you will see the sad state of the covers..



Some of the stuff thats going off to the powdercoaters.. mixed in with some of my YZ125G stuff...






Offline Big Scotty

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Re: New XR75 K1 1974 Project
« Reply #24 on: October 04, 2017, 08:17:13 PM »
Got a rebuild kit for the carb coming,will give that a go and see what happens,fingers crossed
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Offline 80-85 husky

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Re: New XR75 K1 1974 Project
« Reply #25 on: October 04, 2017, 09:07:34 PM »
turn the fuel off and start kicking, if it fires, its leaking into the motor when the tap is on.

full throttle, kick like crazy or push it.

Offline alexbrown64

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Re: New XR75 K1 1974 Project
« Reply #26 on: October 05, 2017, 03:00:36 PM »
Hope the carb rebuild kit works out. When i eventually rebuild the bike for show, i will put the stock carb back on.  I just want it to run hassle free, and the Re-Mx carb works well, looks the same and was cheap enough.

I got up early and pulled the forks apart.  I dont think they have ever been apart in 43 years.  There was just a brown sludge in there and everything was dirty, worn, rusty and in need of an overhaul.  I put degreaser and paint stripper on the legs and washed everything down.
They are easy enough to strip. Pull the dust cap to reveal a circlip. Pull the circlip and then pull the top tube from the bottom. Then just remove the spring and seal etc.
I gave everything another degrease and clean up.

Next was a nice polish and buff of the bottom legs. Cleaned the chrome on the sliders and began reassembly.
I had new Honda OEM seals to go back in, and a few new drain bolts and washers.

I reassembled everything using 110cc of 15W fork oil in each leg.  The forks now look and work pretty good.  Wish people would take  better care of their stuff.  This old girl certainly needed a birthday.  Luckily Honda makes things pretty good quality so the original parts last.



Cheers,


Offline 80-85 husky

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Re: New XR75 K1 1974 Project
« Reply #27 on: October 05, 2017, 04:44:41 PM »
lucky the tubes wernt pitted badly. looking nice and shiny... i got passed in my first race on my Gemini Boss 80 by a k1, thought it was the bike to have...i didnt have the dough >:(

Offline alexbrown64

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Re: New XR75 K1 1974 Project
« Reply #28 on: October 05, 2017, 07:38:10 PM »
Hey Husky, the tubes aren't pitted, but there is a small patch on each leg under the dust cover that has had the chrome worn away smooth.  Hope this doesn't affect the seals too much. Yep, the XR sounds like it was a bargain in todays dollars, but i bet back then they were quite expensive.
Haven't seen the Gemini Boss, but i have a pick of the Gemini Fuji from the same era...



I am going to repaint the tank. Have the 2k paint and decals.  Have to remove a few minor dings and prep everything. I have measured up the location of the decals.  Funny thing is the left and right seem to be about 5mm different from each other.  Maybe the dude in the line that put the stickers on only had to eye them in....



Cheers,


Offline Big Scotty

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Re: New XR75 K1 1974 Project
« Reply #29 on: October 05, 2017, 08:02:59 PM »
Gray alex
My forks were worn in the same spot but really badly,one has a slight bend as well,I bought brand new ones from re mx cheaper than having my old ones rechromed,they look well made and fitted perfect,time will tell if the chrome is any good
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