Skip to main content
000000 000003 000006 000009 000012 000015 000018 000021 000024 000027 000030 000033 000036 000039 000042 000045 000048 000051 000054 000057 000060 000063 000066 000069 000072 000075 000078 000081 000084 000087 000090 000093 000096 000099 000102 000105 000108 000111 000114 000117 000120 000123 000126 000129 000132 000135 000138 000141 000144 000147 000150 000153 000156 000159 000162 000165 000168 000171 000174 000177 000180 000183 000186 000189 000192 000195 000198 000201 000204 000207 000210 000213 000216 000219 000222 000225 000228 000231 000234 000237 000240 000243 000246 000249 000252 000255 000258 000261 000264 000267 000270 000273 000276 000279 000282 000285 000288 000291 000294 000297 000300 000303 000306 000309 000312 000318 000321 000324 000327 000330 000333 000336 000339 000342 000345 000348 000351 000354 000357 000360 000363 000366 000369 000372 000375 000378 000381 000384 000387 000390 000393 000396 000399 000402 000405 000408 000411 000414 000417 000420 000423 000426 000429 000432 000435 000438 000441 000444 000447 000450 000453 000456 000459 000462 000465 000468 000471 000474 000477 000480 000483 000486 000489 000492 000495 000498 000501 000504 000507 000510 000513 000516 000519 000522 000525 000528 000531 000534 000537 000540 000543 000546 000549 000552 000555 000558 000561 000564 000567 000570 000573 000576 000579 000582 000585 000588 000591 000594 000597 000600 000603 000606 000609 000612 000615 000618 000621 000624 000627 000630 000633 000636 000639 000642 000645 000648 000651 000654 000657 000660 000663 000666 000669 000672 000675 000678 000681 000684 000687 000690 000693 000696 000699 000702 000705 000708 000711 000714 000717 000720 000723 000726 000729 000732 000735 000738 000741 000744 000747 000750 000753 000756 000759 000762 000765 000768 000771 000774 000777 000780 000783 000786 000789 000792 000795 000798 000801 000804 000807 000810 000813 000816 000819 000822 000825 000828 000831 000834 000837 000840 000843 000846 000849 000852 000855 000858 000861 000864 000867 000870 000873 000876 000879 000882
English French German Italian Spanish

New member's Navigator



My name is Martin and i live in the Netherlands.

I own a Navigator that i have restored but having some problems with the gearbox (amc).

Hoping for some good info about the problems..

Sorry if my spelling is not so good..

The gearbox locks up when i put it in first gear, and the kickstart shaft also locks up.

Greetings Martin.



Sorry i cant help with the gearbox problems, but i just have to say thats a great looking bike Martin :-)


Hi Martin,

Welcome to Norton Navigator ownership - your bike is looking great and from the look of if close to being finished and on the road once you have sorted the gearbox out.   From your photograph it must be post engine number 106838 with the later gearbox so to help start identifying your gearbox fault I have scanned the relevant three pages of the Norton workshop manual and attached them below (apologies for which way up the pages are!).   You will see that I have highlighted an error in the drawing which is explained on a page not included but it says that the spacer No 34 has been inadvertently reversed in the drawing.

I would start by taking the outer cover off and checking if that is the problem.   If it isn't it is worth checking back through recent threads on problems with Navigator and Electra gearbox assembly and gear selection - you may well find the solution there with the alignment of the selection mechanism.   If you don't have a workshop manual yet I can strongly recommend the one published by Veloce Press ISBN 1-58850-069-1 (picture attached), I would be lost without it!

A final thought, looking at your gear lever it is mounted angled down too far.   I have found that if it is mounted like that it can stick against the outer casing and cause gear selection problems - before you inspect inside it might be worth repositioning it in the horizonal and see if that solves the problem.   Let us know how you progress, there are several gearbox experts in this Lightweight group who have had recent experience of similar problems who are sure to be able to help.



Nicholas and Ian thanks for the respons.

The outer cover is taken off, and i found that the kickstart shaft and the pal where broken..

Ordered the new parts already in the noc shop this afternoon.

The frame is 103275 and engine is 110933 (jubilee)



Hi Martin

welcome to lightweight ownership! I have an early Navigator and late Jubilee and have had both gearboxes apart, they are fairly straightforward if a bit fiddly. Let us know how you get on.



Thanks Dan,

I wil keep posting how i get on.

I also have the original engine with the old type gearbox.

The plan is to rebuild this one and put that back in.

old engine


I pulled out the complete gearbox, and 1 shifterfork has also a litle bit damage.

And the 2 gears in the shifterfork also.

Can't find them in the noc shop.

Anny idea's?

o jee


I believe Russel Motors in London have new selectors, Not sure about gears but you can ask! they are a bit old fashioned so you will have to call, no on-Line ordering! 



As Dan has suggested Russell Motors May be able to help you, Phone number is 0207 228 1714 

Think you will need to start this number with the UK code 44 and not use the first 0 when calling from outside the UK. Hope you get all you need Martin. Looks a Nice bike, and needs to be on the road. All the best.



Hi Martin,

Which bit was broken?

I cannot see your damage on the selector fork - can you supply better pictures to me at, please?

As has been mentioned above - the Layshaft 4th gear is drawn incorrectly in the manuals - you have it shown correctly on the table. Look for wear on the gear, as it will work fitted the other way round, but only half the teeth are in mesh. Your selector gears look past their best - but may still be useable - again, a clear picture would be good.

It looks like you have 1st gear the wrong way round? Can I see the non-kickstart side, please?


Hi Martin,

Its interesting that you have a Navigator with current engine 110933 (Sept ‘64), sat in frame 103275 (May ‘62) – and that you have the original engine 103275 as well.

Did you install the 110933 engine (which as you say, was a Jubilee), or did a previous owner do it?

The reason for asking, is that normally you cannot fit a later engine into an earlier frame, as the rear lower engine mounting bolt fouls the frame – as the engine is ‘fatter’ at that point. The centre stand spring (34) & hanger (40) are therefore different as well.

There is a solution available – and that is to use a later frame member – sometimes called the ‘centre channel or saddle post’ from a later bike – if the outer frame rails are kept for the frame number. Parts 4 and stud 95 are affected by this in attached frame picture.

Are you sure of the frame number? Can you send me a photo of it to verity it is genuine for you?

Likewise, if your frame has been cut, or altered to fit this later engine, you will need to modify it again to accept the original engine. The good news is that all the engine components from 110933 will fit back onto 103275, except the clutch, clutch covers & gearbox – if you want to do that.

However, the oil pump was normally different between the two engines. 103275 would normally have a 3-start oil pump (& worm gear) 110933 would normally have a 6-start oil pump (& worm gear)

So there are a lot of things for you to consider!

Let me know if I can help.


Hi Martin, if it helps my experience with Russell motors is that they prefer to do business the old fashioned way which doesn’t include emails!   I find it is better to phone to make personal contact and explain what you are looking for and then to follow up with a written letter - ideally providing the part numbers which you can find in the appropriate spares book available from the NOC shop.   Once they have the part numbers they will go to their warehouse which is a good few miles away and search through their stock so there will always be a delay.   That said they have always responded in writing within a couple of days and posted the spares as soon as they receive payment by cheque.   Definitely worth the wait though!   Good luck.   Nick


Hi Nick, i've tried to call them several times...

One time i spoke with somebody and they were not very helpfull..

Perhaps is it because i am not englisch.

Just send an email was the answer, so i did..

Very disappointed

And also don't have the numbers of the parts i need.




Hi Martin,

I would persevere, they can be rather old fashioned in the way they do business and I have always found a phone call armed with the parts numbers is the best way to make progress.   You can buy a photocopy of the later 1964 onwards Jubilee and Navigator spares book from the NOC shop.  Click on the Lightweight twins icon then scroll down to 'spares lists' and you will find the right one listed there - I have attached a picture from the appropriate shop page which has the price and shop reference number LWT64.   I have found the spares list as invaluable.  Good luck!   Nick      



If you cannot find the parts in the UK or anywhere else in Europe, send me an email with the part numbers and I will check my sources here in Northern California.

My direct email address is




Hi Martin,

You may by now have had excellent advice from Andy Sochanic. 

I can't see from the photos and the wear any reason why the gearbox should lock up when selecting first gear.

The selector drum has a gear on the end and one tooth is very faintly marked. From memory there is a similar mark on the driving quadrant gear of the gear indicator shaft. In the neutral position the marks are aligned.

In my experience, this is very difficult to achieve and to check. One tooth displacement will either give you gears 1 to 3 and 4 will not go in. Or gears N to 4 and 1st will not engage.

Even with the wear you indicate, total lock-up should not occur.

As you tighten the 5 securing nuts for the inner plate, check nothing is getting jammed. When secured, check you have a working kickstart and ratchet by slipping the kickstart onto the splines and rotating gently by hand. Layshaft free to turn? Mainshaft free? Sleeve gear/cluch free? 

Make sure the gear selector shaft spring engages with the pin on the inner plate as you gently add the outer cover. Loose fitted you can check the gear action by slipping the gear lever onto the splines and try changing gear. Can you feel the detent coming out of neutral position and into 1st or 2nd  position? Is it about the same movement to change up a gear and down a gear? You may have to rotate the gearbox sprocket while changing gear or the dogs will baulk. Do this by having the bike on centre stand and rotate back wheel at same time as selecting different gear.

If you can't achieve 1st or 4th gear, there is nothing else for it. You must remove the inner plate and try again and make sure those gears are correctly aligned. If you find the original alignment marks, put white paint on each end of the marked gear, and mark the correct place on the quadrant gear too.

Even a worn gearbox should go through the shift pattern. I'm urging you to have another try.



Hello Martin,

All your components show a small amount of wear - But I would be happy to use them again.

Some good advice above already. Always keep the oil level up to the mark. And always use the NOC square section 'O' rings - well oiled on assembly. If they are dry, they grip amazingly!

Also, from what I can see, your inner cover looks in good condition - the kickstart 'stop' looks fine.

When assembling the gearbox, ensure your bushes (part 48) are a good fit, with no slop. If they are a good fit, then remove all traces of oil from the casing and the outside of the bush, apply Loctite bearing fit and press home, taking care to line up any oilways. Also ensure the bush at the end of the layshaft is pegged to ensure it does not rotate.

Also - remove the detent plunger (parts 24, 25, 26) to assist you - only replace them once the inner cover is safely on.

I have just noticed that Part 24 is incorrectly shown. It should be wedge shaped at the top - not pointed - and I cannot see yours on display. (My stuff is in a lock-up miles from here at present - photo to follow).

Looks like NOC Spares have them incorrectly identified as well. Early plunger (pointed) = PNo 042835 and the later one, like yours (wedge shaped) is PNo 040034.

Assembly instructions attached - from an Electra Owners Manual.

Let me know on if you need any more information.

late bush pegged


Thanks for the feedback,

First, the lock up of the gearbox was the kickstartpal and the kickstartshaft.

Already have new parts from the noc shop.

The bushes are inspected and good, and fitted with loctite.

Part 24 is pointed in my gearbox.



I had my first test ride today, so far so good.

In the coming days i wil make some more test runs.

Now parked with the other bikes.



Did you manage to get selectors from Russel motors, the sold one to me at the end of last year. 



No Dan, i sent them an email but they did not have the decency to react..

On Andy's advice i used the old ones.

Had all the springs in the mechanism replaced by new ones and 2 new gears from the noc shop.


In reply to by martin_woltman


Hi Martin (& Dan), interesting comment ref Russell Motors.  I sent them a letter 5-6 weeks ago requesting gearbox parts (with numbers) and tried phoning at same time but had no response from them at all.  It could be they’ve stopped trading temporarily with all this virus “stuff” about? Bruce


Norton Owners Club Website by White-Hot Design

Privacy Policy