RD250LC Project

[Robgvx]

In my opinion, if you have the cylinders off you might as well replace the rings and small end bearings, and of course all gaskets. The parts are peanuts in the overall scheme of things (assuming that they are available of course) so don't cut corners while you are doing a nice job on the rest of the bike.

If it was me I would see if oversize piston kits were available and re-bore too. Then you know the top end is basically new.

Actually, if it was me (and having followed the F40LM thread!) I'd probably split and strip the cases and go for vapour blasting too but I can understand if you didn't want to go that route.

 

[Mike01606]

looks just fab :thumbsup:

Thanks Mark.....it's coming together quickly now.

In my opinion, if you have the cylinders off you might as well replace the rings and small end bearings, and of course all gaskets. The parts are peanuts in the overall scheme of things (assuming that they are available of course) so don't cut corners while you are doing a nice job on the rest of the bike.

If it was me I would see if oversize piston kits were available and re-bore too. Then you know the top end is basically new.

Actually, if it was me (and having followed the F40LM thread!) I'd probably split and strip the cases and go for vapour blasting too but I can understand if you didn't want to go that route.

I agree with most of this Rob.

I'm ringing the main agent this morning to try and buy rings, little ends and a top set.
Although the bike will be a good standard it will still require a bit of work so splitting the cases will open up another major work front!
I will run to the MOT centre then change the oil and hopefully all of the oil seals are intact.

I'm also looking for a genuine 1st oversize piston kit and will probably rebore over winter.

Time is a bit of an issue as it has to be complete by early June. I want to MOT it when I'm off in early May then if anything appears I've got time to sort.

M

 

[PAUL V]

Regarding the cylinders,

You really need to get them measured properly by someone who knows how you do it :thumbsup:





Only then will you know how worn they are, ring end gap is not going to tell you of the bore is oval or worn tapered.

IF the cylinders are "OK" then you really should hone them before you fit new rings but then this may take the cylinders past its service limit.



Regarding the pistons and re-bore, i have just checked stock and there are no decent aftermarket "made in Japan" pistons available at the moment, only cheap Chinese / Taiwan s#it that i would not fit to be honest.

You have to be careful buying pistons before you get them measured as it may not clean up on the 1st over size !

I know time is important but you would be best getting them bored now and build the engine up and leave it alone. I can offer a quick turnaround on the Re-bores and even give the cylinders and head a vapor blast for you if it helps.

Check what pistons you can get and let me know if you need any help.

 

[Robgvx]

Thanks Mark.....it's coming together quickly now.



I agree with most of this Rob.

I'm ringing the main agent this morning to try and buy rings, little ends and a top set.
Although the bike will be a good standard it will still require a bit of work so splitting the cases will open up another major work front!
I will run to the MOT centre then change the oil and hopefully all of the oil seals are intact.

I'm also looking for a genuine 1st oversize piston kit and will probably rebore over winter.

Time is a bit of an issue as it has to be complete by early June. I want to MOT it when I'm off in early May then if anything appears I've got time to sort.

M

Wiseco appear to do 'Prox' pistons for a 1980 RD250LC: http://www.wiseco.com/ProductSearch.aspx

 

[Mike01606]

Paul, you have mail!.......M

 

[Mike01606]

Wiseco appear to do 'Prox' pistons for a 1980 RD250LC: http://www.wiseco.com/ProductSearch.aspx

Thanks Rob,

Genuine ones are NLA but about £110 each with rings.....

A genuine head gasket is also £60 so I don't to be taking it on and off!

M

 

[Mike01606]

Last night was too nice to work on bikes so the 360 came out. 300 miles this week as it's become my daily while the sun in shining......

I got in touch with PaulV yesterday and the entire top end is now winging it's way to Wolverhampton to let the pro's look at it.....

Before packing cleaned the residual gaskets off the other cylinder and head.



The head and both barrels has some residue at the middle front.
I left it is place on one. I'm not sure if it is from the front wheel or a coolant leak.





Ready for packing



The biggest challenge of the build to date was finding a box that would tightly take them!
A large box, bubble wrap, a Stanley knife blade and two rolls of case tape later....Result!



Finally a big thanks to Paul for the advice and help as sorting it correctly the first time is the right way to go......

 

[Mike01606]

With the top end on its way to Paul I has a number of little jobs to do tonight.....

First up, clean the head bolts. They had quite a bit if scale on them.



I removed the course stuff with Scotchbrite and WD then put them in the USB for 10 minutes.
It's really good practise to prep stuff ahead of when you need it as it makes reassembly so much cleaner and more pleasant.



Whilst I had the USB out I cleaned up the hose clips.
I had to cut one to get it off but managed to buy some scabby ones off the bay of E.

From these I need to make up 6 good ones. I was going to get the yellow passivised but the olive drab is good enough for the ones that show . Currently work in progress.



When the light went I moved indoors and reassembled some more parts onto the frame including the clocks and LH controls.




I've also fitted the rear light unit
and number plate holder.



Finally for tonight a couple of parcels arrived including a new Yuasa battery and acid.



I tried it for fit to make sure it is the correct one as it is one of the last things I'll install.

 

[Mike01606]

Firstly apologies for all of the typo's in the thread. It is a mixture of autocorrect and eyesight not good enough for a phone!

One of tonight's jobs was to seat the tyres properly on the beads.
I bought some tyre lube and applied it to the beads then overinflated them to pop them on.
The tyres have a yellow dot that should be placed at the valve to aid balance.

 

[Mike01606]

Another job was to mount the rear sprocket. First I needed to grease the bearings and fit a new hub seal as the original one was damaged.





Next up was mounting the sprocket, spacer and circlip.



I'm actually reusing the front and rear sprockets as I had the rear one replated and it looks in really good condition. My mate (who sold me the bike) read somewhere that it is an OEM one which is very sought after.
The bike came without a chain so I will make a final decision when I'm ready to fit one. Hence I did not fold over the new locking tabs.

 

[Mike01606]

Front brake disc time. The one on the bike was completely knackered from being used with a seized caliper. The bike came with another disc that had minimal wear





A quick clean with wire wool, scotchbrite and WD and it is ready to mount.



It isn't perfect but I do want to keep a bit a patina.

Final shots of the night........





I took a cheeky shot with the tinware fitted but I will save that for the reveal

A teaser for now. A new cover from Aldi. £8.99....proper VFM

 

[Mike01606]

I'm really cracking on now and it feels like it is coming together quickly. Like anything though it is the little details that take the time.

I cleaned up the right footrest hanger tonight using the same process as the fork legs.





It only took about 45 minutes to get it to where I wanted it.



Then it was onto the bike. I fitted the torque arm first which was a pig to fit as the frame end slid between two lugs so I effectively I had 4 thicknesses of powder coat to shave down. This took about 45 minutes in itself as I didn't want to get to bare metal. What did I say about the little details!



After that was fitted it was a matter of bolting on the hanger and attaching the refurbished rear pegs and brake lever.



The front pegs still need a lot if work. I have new rubbers but there is quite a bit of corrosion on the metal parts.





I've another two days on my own so I'm aiming to get quite a bit done tomorrow but I also think the 369 will get a good outing.....let's see how I get on.....

 

[Mike01606]

Insurance

I actually insured the bike yesterday now it isn't scattered all over the place.

I was pleasantly surprised at the cover available. I've had a full license for close to 30 years but bot had bike insurance since 1995.
For an agreed value policy, 5k miles per year, fully comp, SDP and commuting to a single place of work, TP cover on any bike not belonging to me and track day cover (for bikes >20 years old).....£111 through Carole Nash. I thought that was pretty good. :thumbsup:

 

[Mike01606]

Pretty much tinkered all day today apart from a visit up to my folks.....

I've been working on a number of parts. It's been slow progress but the beauty of doing this type of stuff yourself is that your time is free so you can work to the finish you need.

I cut the rubbers off the foot pegs. There is no way the old rubber was going to come off in one piece.



The metal under the rubber was in good nick and still green. The hinge is peened over and has to be drilled out. You can buy replacement pins but I've never seen a good finish. In fact eBay is full of people selling them on as the have replaced the full peg.

I decided to mask off what I could and paint with zinc primer and satin black. I will then treat the green metal and fit the new rubbers tomorrow.

 

[markst]

how much do you think you have spent so far ???

 

[Mike01606]

The main job today was the front brake. The master cylinder looks like it had been topped up with a watering can!





I need to strip it down completely. It was a bit fiddly, especially getting the sight glass out but the only damage was to the gaiter which was perished.



With all of the orifices and non painted surfaces masked I started to paint with PJ1 satin black. I painted the caliper also which I bought as a spare off eBay as the original was completely rashed from being in a vice. Have some people never heard of soft jaws.





The reservoir top is difficult to replace. The pattern ones do not have the same writing on, so I cleaned it properly and used several thin coats.

All in all I applied about 5 coats at 10 minute intervals. The paint runs quite easily so you need to apply in warm weather and not too thick.





Once the paint had touch dried I removed the masking tape and hung in the conservatory. I'm really impressed I've managed to leave them alone. The paint should cure fully overnight.

I also painted the centre of the horn. The outside is still olive drab and even though there is some rust it is well worth retaining. I treated the olive drab with race glaze jet laq.



The radiator is in exceptional condition but while I had the satin paint out, I masked the outside and misted the fins front and back then cleaned the rest with scotchbrite and WD.

Before



After





...and on the bike..



The radiator cap, like the brake reservoir is difficult to replace with a good one. I cleaned it with some very fine wire wool and WD and the treated with jet laq.



I need a few parts to completely assemble the front brake including a piston. I have two pistons and one not too bad but both have pits in the surface in the area of the seal.

A day off tomorrow...........

 

[Mike01606]

how much do you think you have spent so far ???

About as much as Tim spends on his LM before brew time on a typical day ....

When I had a look last week. I'd spent about £750 to date. I haven't got a clue what the market value of one in this condition is but I think it will owe me more than it's worth in the end. I intend to keep it forever and make it better so value isn't an issue.

The one thing that would really hurt now would be a leaking tank. It looks fine but if you go back to the carb cleaning post that was rust out of the tank. Left carb only as it sits on the side stand.

If it is gone it is not only the cost but the time I will be without it. The intent is to use it from my 50th onwards and the wait is about 2 months.

 

[Mike01606]

After not thinking id get near it yesterday I made some great progress....

The brake parts I'd painted still needed to be cured fully.



My Daughter thought it was hilarious and proceeded to txt my wife "dads cooking motorbike parts in the oven" ...Brilliant!

I must say that when cured the paint finish is excellent and I built up the caliper and test fitted it. It is shown with a new banjo union and bleed nipple but I still need a piston and seals.





I'd painted the foot pegs in zinc primer and satin black. Now it was dry, I treated them with jet laq, fitted the new genuine rubbers and on they went.

View attachment 134328



The right hand one has a spring retainer that holds it out of the way for kick starting.



I just know I'll keep forgetting that already!

I also built up the refurbished master cylinder and dry fitted it. It needs to come off again for new screws and seals so I will photograph properly then.



The rest of the day I spent mounting all of the remaining parts and had a good clear out.

The horn.....



The right hand controls were tricky as I had to remove a lot of powder coat to get them sat properly....each to a different level. This is where all the time goes as corners can't be cut.
The throttle part I took to bare metal as per the the factory bars. You cannot tolerate any stiction as you only have three weak springs in the carbs and oil pump to shut the throttle.






I then mounted the new indicators and all of the painted panels to give it a good clean and polish......







I hope your still enjoying it......

 

[markst]

wow ...what a great looking machine :thumbsup:

 

[Pangea]

Nice job. :thumbsup: