Well and truly Stuck! Progress report and tales of woe

Hi guys,

Got a couple of Q's, now that I've finally got my project underway. (1971 750 commando)

I took the engine plates out at the w/e, found to my horror the swing arm spindle has well and truly seized in situe. Tried an overnight soak in penetrating oil, tried winding in the front isolatic bolt and put a spanner on the lock nut to try to twist the thing free...No chance. Even tried shocking the thing with a copper bar and a big hammer and gave it a good few clouts. Oh...I did take out the locking bolt btw It just seems to be stuck in the section, where it passes through the engine plates. I'm quite tempted to scrap the engine plates as some bright soul decided to fit a seperate oil filter under the swing arm spindle. Not a bad idea in principle, tho very badly executed. There are four holes drilled very close together, are about 1/2", where I can only guess various attempts at mounting the thing...It's a right dogs breakfast.

The only thing I've not tried so far is getting a blow lamp on the engine plates, see if the heat will un stick things. I wanted your advice before proceeding with this as I'm not sure if the heat will distort the plates?

Also, having finally gotten the frame free of components I had a look to see what the over all state of the frame was. It's bent. :roll: The main spine looks to have a very mild bend + the headstock has a 1, or 2 degree twist anti-clockwise, when looking from the front. Add to that the bodged repairs to the prop stand lug. They both need cutting off and replacing with a good one.


I also had the front isolatic apart yesterday, found that the rubbers don't seem to be standard items...Were there any aftermarket items made? It is a piece of 1/2" pipe, with a one piece set of rubber disks spaced across the pipe.


Just as well I like a challenge, eh? :shock:

Cheers,

H

Yes they can be very hard to remove, especially if it's the original. Heat will help and it's unlikely to distort the side plates. What will help is to sacrifice the main stud or find another with the same thread and bend it 90 deg. Screw that into the Rh side with a locknut in between and use it for leverage to rotate the pin and pull it out once you get it moving. That might work otherwise it's the hacksaw method which can only cause secondary damage as I see it. That still leaves you with a seized pin to remove although it'll be on the bench by then. Soak that pin for more than just overnight (fill up the tube completely) and try again with heat and the stud/wrench method. See pics for how I bent the stud.

Keith — that's a novel way of rotating the pivot.
Hegel — mine was as stuck as yours. I got a length of high tensile 1/2 inch UNF bar and several nuts and made a puller with a tube that fitted over the end of the swinging arm. Once the threaded bar has bottomed in the threads of the spindle, you have a chance of turning it and, as Keith has shown, that definitely helps. Heat helps and a few days of soaking in penetrating oil should help as well. Have a look at this Old Britts link:

http://www.oldbritts.com/ob_start.html

Click on "Technical Articles" and then click on "Removing the swinging arm spindle".

Mine gave way very slowly, a millimetre at a time. I cracked a 1/2" drive socket doing it but I managed to get it out eventually. Chances are that when you do manage to extract the beggar, the bore of the tube in the cradle will be oversize. You have three options then: 1. Buy a new cradle; 2. Fit Heinz Kegler swing arm lock rings (works well); 3. Fit an oversize spindle.

Good luck and let us know how you get on!

Alternately, with engine and gearbox removed you can extract the cradle assembly and have the spindle pressed out by someone with an arbor press.

I guess I got lucky, mine slipped out with finger pressure.

Alternately, with engine and gearbox removed you can extract the cradle assembly and have the spindle pressed out by someone with an arbor press.

Click to expand...

Be careful with this and take it to someone you trust. A friend took his too the local Harley chopper shop. They returned him a swingarm that looked like a pretzel and the engine mount plates had to be straightened before he could refit the crankcases!

Hi guys,

Thanks all for your replies/advice and photos! I'll break out the blow torch and see if I can loosen of the rust on the inside. I've hashed together a few pics on the photobucket site, for you to see. I'll add more as I progress..Or not, lol :roll:

http://s713.photobucket.com/albums/ww134/Hegel_B/

Daveh,

Thanks for the link. I see from the link the guys/guys who've owned the bike before me have tried both the propstand mod and the oil filter mod and ****ed it right up on both. As you'll see on the pics the holes drilled on the engine plates are right carnage

I also put the front isolastic pics on the site, are rusty and seem to have parts missing...Well according to both the factory manual and the parts lists anyway.

Have a look, see what you think. Be interested to know your thoughts

ATB,

H

Oh...I forgot to add. I've got the Norton factory puller. I'll also try making a puller with a socket and a nut.

Cheers again,

H

Does the front ISO tube have bonded rubbers? If so someone might have modded a Mk3 mount and cut off the threaded ends. Pre Mk3 are bonded main rubbers and buffers each on a separate piece of tubing. Good luck.

Hegel — I see how the PO has bodged the rear of the cradle. It can be repaired but only on the bench. The holes can be filled in with weld and filed and sanded down to a nice finish. New holes can then be drilled in the correct locations. When you have extracted the spindle (and you will!), clean any rust and grease from the tube and remove surface corrosion from the spindle thoroughly. Then introduce the clean spindle into the clean tube. If there is any perceptible 'rock' in the tube, then the tube is oval and the swinging arm will have play, no matter how good your bushes are. This is a no-no. It can be sorted by swing arm lock rings. Have a look at this link:

http://www.nortonfastback.com/html/mods.html

They are well made and eliminate play between spindle and tube. Alternatively, you may choose to fit a new cradle, spindle and bushes.

Re the isolastics, unless you don't mind maintaining the shimmed assemblies, I think you should scrap them and fit vernier isolastics. Many owners confirm this. Seeing as you have dismantled the bike that far, it is probably a good time to do this. I know it's yet more money but it's worth it!

I can't comment on the side stand mod — I have no experience of this.

Good that you have the factory tool.

I hope the above is helpful.

Keep us informed.

Dave

God yes, do the vernier isolastics now. They undoubtedly need doing, and it's a lot easier with the bike dissassembled. I did them on the FRONT only and I thought I was gonna need a frame spreader to fit them in... PITA.

It's also possible to use penetrating oil inside and do a slide hammer adapter.
Have an expert look at your frame neck. I've seen at least two that had a slight angle I was told were for crowned roads.

Brian K

God yes, do the vernier isolastics now. They undoubtedly need doing, and it's a lot easier with the bike dissassembled. I did them on the FRONT only and I thought I was gonna need a frame spreader to fit them in... PITA.

Click to expand...

Did you cut down the right side of the tube before installing the Mk3 isos?

Hi again


Keith1069,

Yes! They are...Or rather, were bonded...Ahem I guess they were the Mk3 rubbers...I kind of killed it in the process of removing the thing.

Regarding the vernier Isolastics, how many of you have this mod? Easy to fit/maintain? I don't seem to be able to find a whole lot of info, other than the advertising bumf.

Fortunately I have a couple of shops that are quite close to me, one I have already had dealing with, the other was reccomended to me;


http://motorcycle-frame-straightening.co.uk/

http://www.fdmotorcycles.co.uk/

Unfortunately I can't get the frame straightened until I've sorted out the engine plates/swing arm, since they need them for their jig. I've got work up to my eyeballs for the next week, so it'll have to wait 'till I get back. Fustrating really, as I'm having so much fun with it all.

Speaking of frames....If it turned out it was un repairable...Is it still possible to get a new one?

Cheers

H

You can get the Norvil conversion 066130A and 066131A from their distributor I think www.fairsparesamerica.com or direct www.norvilmotorcycle.co.uk. There are no modifications needed assuming your front mount is not a Mk3 already. You should have the tube extending more from the RH than LH. If both sides are the same it is a MK3 mount and we can only guess what the PO did!
They work well but installation of the assys is not as easy since they have to be assembled complete and it's tight. With the old style you could just slide in the end caps last.
New frames are available, see Norvil site.

Hi Guys,

Certainly not a speedy rebuild this one, lol. Finally managed to get the swing arm spindle out. A work collegues father owns a garage, so we used the 30 ton press to get the little mite out. It took somewhere in between 4 and 10 tons to push the sucker out, fought us all the way out. Not bad for a 'nice sliding fit', eh?

The only thing that conserns me at the moment is the LHS bush is a somewhat sloppy fit, I'm not sure wether it's the bushes fault, or the swing arm pivot tube has become oversize....

Thoughts?

ATb

H

Re:

Hegel said:

Speaking of frames....If it turned out it was un repairable...Is it still possible to get a new one?

Cheers

H

Click to expand...

New are approx. US$1200 (dunno where you are) and used are somewhere around US$500 or less.

swooshdave,

Thanks

I'm in the Uk. I had a look at the Norvil site, a new frame is £624...Not sure if that's including tax? Expensive...But at least they're still available, if worst came to worst. I was looking at the fame at the w/e. I'm pretty sure they could straighten it out.

Cheers again,

H

The clamp-on swingarm pivot anchor fix is the ticket.

a search will turn it up, or a quick reply from several on here who have 'em...

GrandPaul,

I'm intrigued, not heard of one before. O.k I'll have a search, if anyone here has one I'd be interested.

Thanks!

H

If it's totally disassembled is there any reason not to just drill a couple of holes and weld on nuts?