[Rattlebattle]

I have decided to change the gearbox sprocket on my 2015 LE Despatch (C5 in fancy dress) to one with an extra tooth to make main road cruising less vibes. I have the new sprocket and chain, a r/h side engine cover gasket, kickstart shaft oil seal and oil filter and associated O rings etc. I also have the factory box spanner to undo the sprocket nut; I have an adjustable puller so didn’t buy the factory sprocket puller. The procedure in the workshop manual appears to be straightforward but I was just wondering whether or not there are any pitfalls I should avoid? Thanks.

[Rattlebattle]

Forgot to ask whether I need to drain all the oil or just replace what is lost through removing the r/h cover? I was only 500 miles ago since I chang d the oil and filter. I am a competent amateur mechanic with a good selection of tools but no bike bench.

[Cidrolin]

About the gearbox sprocket change I didn't made this before so I don't know about pitfulls in it...
About the RH cover removal I do suggest to completely drain the oil from the 3 drain points (or 2, if your bike is before 2016, I think) and then use it again because with 500km is almost new.
Bye

[longstrokeclassic]

Did mine last month. I  ran the bike up onto some 2" thick timber and carefully worked on it while it was on the side stand with all the oil out of the way.
Front wheel was hard against a wall and the rear chocked in place to avoid any unpleasant surprises while swapping over the sprocket. I lost no more than half a cupful of oil from the right hand side casing web work. I carried out an oil change then decided to do the sprocket swap
 Just keep looking down between the cases as you close them back up to ensure the oil pump O ring is still in place, I held the new one in place with a dab of grease.

[Rattlebattle]

Thanks for the replies. Portisheadric - should I fit a new pump oil seal or can I reuse the old one? The bike has clocked just over 3,000 miles. Likewise, should I fit a new kickstart seal. Mine doesn’t leak. I had wondered if I could do the job on the sidestand.

Thanks.

[malky]

Thanks for the replies. Portisheadric - should I fit a new pump oil seal or can I reuse the old one? The bike has clocked just over 3,000 miles. Likewise, should I fit a new kickstart seal. Mine doesn’t leak. I had wondered if I could do the job on the sidestand.

Thanks.

Here's an idea of what's ahead.

https://www.youtube.com/watch?app=desktop&persist_app=1&noapp=1&v=gNK9tfJ1_xc

Personally, for piece to mind, I would replace the seal's, but that's me being fussy, I've got a set of PTFE "seal tubes" which makes damage on removal/replacement less likely as well.

[Narada]

I've had my r/s cover off a few times now, and have been using the center stand with a 2X4 under the right foot of stand.

Having the bike near a wall and unable to roll is a good plan too. Be very aware this is a bit precarious while woking. Do not let it tip, or roll forward! 

I have not yet changed my cover gasket, kick start seal, or rubber o-ring, and all is well. My o-ring was flat on the back side, that's worked ok. I just grease and re-use.

Watch that you don't block the oil passage at top of cover, or goob it with silicone! 

Also, be sure the black plastic gear selector shaft piece is in place, before replacing cover, and if you try to shift gears with cover off your linkage could go wonky, due to loose shaft. Yes, I've done that a couple of times now. 

[Arizoni]

Like portisheadric said, it is a small O-ring so it can be reused.  Just use a dab of thick grease to hold it in place while you fuss with reinstalling the sidecover.

It might also be a good idea to have a small block of wood to jam between the chain and the sprocket teeth to keep things from moving while you loosen the nut.
It can be pretty tight.

As for the oil question, I wouldn't have a second thought about leaving it in the engine and just replacing the little bit of oil that spills out of the sidecover once I had everything back together.
Just make sure none of the oil, dirt and crap that has been thrown off of the chain onto the housing doesn't get inside the "clean" areas of the engine.

[Rattlebattle]

OK thanks guys; that’s great. It always helps to hear from people who’ve done the job. Thanks again.

[gashousegorilla]

  A 1 13/16" socket and impact gun will zip that nut right off.....

[Rattlebattle]

You must be an economist as well as ace mechanic. “Assume you have an impact gun”.  Sadly I don’t
I believe though that I have a suitable socket, bought when I had a Triumph Sprint GT, used for loosening the big nut holding on the wheel. That and a breaker bar should do it, I hope. Can’t see the official box spanner doing much good; I should have saved my money.....

[heloego]

   I spent the $$ for a "complete set" of "factory" tools from a reputable vendor online. Some are workable. Some are total crap, to be replaced as needed, mostly due to the low-quality steel used in their manufacture.
   Still, always a good investment to have a modest air compressor and air tools handy.
   

[Rattlebattle]

Yes, I’m sure powered kit would be great but at my age I don’t think I’d get value as I now only maintain my two bikes, both bought new by me. Next time I’ll check here before ordering factory tools. Nobody has mentioned using anything to extract the sprocket itself so I’m glad I didn’t buy the extractor, which is expensive. I might try using the box spanner on the sprocket nut - maybe it’ll be more effective than a breaker bar if I clout whatever I fit in the box spanner with a hammer to shock the sprocket off. I’ll manage, I’m sure. Thanks for your input. BTW is it really necessary to remove the battery and tray to disconnect the generator wires on a C5? And the footrest? Neither is mentioned in my C5 w/shop manual.

[Rattlebattle]

Forgot to say that while I’m in there I might as well
remove the auto-decompressor. I’ll let you all know how I get on with these jobs, though it’ll be a while before I have time to do them.

[Narada]

Just follow the wires coming out of the top of your cover to a couple of plugs behind the motor.

Mine were tucked into the middle of the frame and were a little short. If the plugs reached higher out of the frame area it would be a little easier to disconnect them.

[Rattlebattle]

Thanks.

[hpwaco]

Was putting the gearbox in gear and applying the rear brake mentioned?

[Rattlebattle]

Well, I have replaced the sprocket but not yet put the cover back because I wanted to sort out the rear brake and so can’t finish the original job until I have the new rear chain fitted. Job was easy enough. There was enough slack to unplug the two connectors once I had removed the air filter cover unique to the LE Despatch. I removed the footrest, which was easy anyway. I used the factory gearbox nut extractor - a big box spanner - shocking it off with a hammer on the rod I used as a lever, locking on the rear brake. Simple.
The original rear chain, though an O ring, was in a terrible state with various stiff sections. A new Renolds is to replace it.
Before I can finish I need advice on the rear brake. This has never worked at all. Neither of the brake shoes appears to make much contact with the drum despite being adjusted properly when on the bike. Should the pivot cam ie the one at the opposite end of the operating cam screw into the brake plate and be solidly mounted or should it be free to move. I get the impression that the shoes are not centralised even though when adjusting the chain I have followed advice to tighten the brake adjuster really tight before tightening the spindle and brake plate nuts. It must be possible to make the brake work to some extent; as it is it shouldn’t pass an MOT test. What should I do now that the brake plate is off the bike?

Thanks in advance.

[Jako]

Something to consider    https://youtu.be/gHRm_t_8DYE

[wildbill]

I don't think that guy's mod is recommended -its classed as unsafe

[Arizoni]

Rattlebattle
IMO, the pivot bolts should be tight.
There is quite a bit of room for the backing plate that carries the shoes to move around and the trick is to take advantage of it.

After everything is assembled but while both of the rear axle nuts and the anchor nut is loose, tighten up the brake rod adjustment nut until the rear wheel brake keeps the wheel from moving.  Give the backing plate a few light taps with something like a piece of wood or a large screw driver handle to help it move to a position that allows both break shoes to centralize inside the brake drum.

Then, tighten the anchor nut and both of the axle nuts.

You can now back off the break rod adjustment nut to get the brake pedal travel you want.

I think after doing this, "adjustment" you will find the rear break works a lot better although even at its best, it takes a pretty hard stomp on the brake pedal to lock up the rear wheel.

[Rattlebattle]

Thanks; that’s pretty much what I do except for the bit about tapping the brake plate. I’ll try again when I get back to it. Do you know where the large flat washer fits on the axle? It’s not the anchor bolt one. I’m afraid I didn’t note it down and the manual is no use. Oh for an exploded diagram....

Thanks

[johno]

I have mine floating, I changed the original nuts and washers for nylocks, don't forget to add a smear of copper grease to the backplate to stop it from seizing with heat and corrosion later on. Over 10,000 miles and no issues and every UK MOT passed also with out issue.

[Rattlebattle]

Thanks Johno; I think I’ll do the same. My brake has never worked at all, as evidenced by the total lack of brake dust and wear on the shoes. BTW I’ve found where the large washer fits, courtesy oh Hitchcock’s online parts book. Hopefully now I can put it all back together and enjoy more relaxed cruising on main roads and have a rear brake that does something. I hadn’t realised that the OEM chain is an O ring one, though I don’t think much of the quality. There was a small crack in the original sprocket too. I’ve replaced it with a British one.

[longstrokeclassic]

One way of testing if your shoes are central is to do the following...
Put the brake plate over the stub axle and into the drum. Apply the brake and turn the assembly over so the four 'feet' face down. If the shoes/brake plate assembly is central the clearance between the brake plate and the stub axle will allow the axle to either fall or be pushed out of the ball race. If only one shoe is touching the axle will be held in place by that shoe and the hole through the centre of the brake plate.

[longstrokeclassic]

One problem I found with mine was the brake cam had not been machined square to its shaft so when new the brake shoes only made contact at their edges. I reprofiled the cam which improved the contact area. Now that the full surface area of both shoes make contact with the drum it's works very effectively.

[Rattlebattle]

All back together now. I just need to refit drain screws and filter and replace the oil. In the end I dismantled the entire brake, gave it a good clean and centralised the shoes by tightening the adjuster as much as I could to lock the brake before tightening the axle nuts and brake stay but. It does seem a lot better but it’ll need a test ride to tell. Effectively it’s a new brake so it should get better after a few hundred miles as the shoes finally bed in. I just hope the gearing change is worth it.  I was a bit surprised that the sprocket just pulled off. Glad I didn’t buy the factory puller. I need not have bought the box spanner either because I already have a 46mm socket.... Oh well, you live and learn. Thanks to all who offered advice; much appreciated.

[Rattlebattle]

Went for a test ride today. It seems much happier with the raised gearing. The rear brake, though by no means powerful, at least now works properly. With the floating shoes it should now bed in and I expect it will get better. All in all I’m pleased with the mods; the higher gearing means that it is now much smoother at reasonable main road cruising speeds, albeit at the sacrifice of a little flexibility in urban limits. Definitely worth the trade-off for me, though I suspect if one lives in a hilly area and/or frequently rides with a pillion the standard gearing would be better. Anyway, job done and thanks again to all those who offered advice.

[jefrs]

Well, I have replaced the sprocket but not yet put the cover back because I wanted to sort out the rear brake and so can’t finish the original job until I have the new rear chain fitted. Job was easy enough. There was enough slack to unplug the two connectors once I had removed the air filter cover unique to the LE Despatch. I removed the footrest, which was easy anyway. I used the factory gearbox nut extractor - a big box spanner - shocking it off with a hammer on the rod I used as a lever, locking on the rear brake. Simple.
The original rear chain, though an O ring, was in a terrible state with various stiff sections. A new Renolds is to replace it.
Before I can finish I need advice on the rear brake. This has never worked at all. Neither of the brake shoes appears to make much contact with the drum despite being adjusted properly when on the bike. Should the pivot cam ie the one at the opposite end of the operating cam screw into the brake plate and be solidly mounted or should it be free to move. I get the impression that the shoes are not centralised even though when adjusting the chain I have followed advice to tighten the brake adjuster really tight before tightening the spindle and brake plate nuts. It must be possible to make the brake work to some extent; as it is it shouldn’t pass an MOT test. What should I do now that the brake plate is off the bike?

Thanks in advance.

Take the cam/bush off the brake plate and reassemble so it slides. Nip the bolts up and set the lock nuts. It has lock nuts and elongated holes because it was designed to slide not be painted in place! The bolts must not be too loose or it will adjust over every bump.  I found I had to set the bolts tight enough so only my weight on the brake pedal shifted it. But the bolts are small so that was just nipped up using a nut-driver. Now the shoes will centralise when the brake is applied hard and then the brake rod can be adjusted, and because it is now consistent, so there is very little movement needed on the brake pedal. The rear now feathers perfectly, a very effective rear brake.

[Rattlebattle]

If you read my later posts you'll find that I did just that, some time ago now. Thanks anyway.

[Fragman]

Rattlebattle
IMO, the pivot bolts should be tight.
There is quite a bit of room for the backing plate that carries the shoes to move around and the trick is to take advantage of it.

After everything is assembled but while both of the rear axle nuts and the anchor nut is loose, tighten up the brake rod adjustment nut until the rear wheel brake keeps the wheel from moving.  Give the backing plate a few light taps with something like a piece of wood or a large screw driver handle to help it move to a position that allows both break shoes to centralize inside the brake drum.

Then, tighten the anchor nut and both of the axle nuts.

You can now back off the break rod adjustment nut to get the brake pedal travel you want.

I think after doing this, "adjustment" you will find the rear break works a lot better although even at its best, it takes a pretty hard stomp on the brake pedal to lock up the rear wheel.

Sound advice on the brake setup method & I used it the other day when I fitted my new EK
x-ring on my unit. Anyone having an RE with the factory, shyte chain should bin the bastard straight off and get a known quality unit fitted ASAP! (Fookin' can't figger out why I left the stock one on for 11,000+km...Dumb.)

Ye know yer chain is a worthless pile when it can stand on its' own.

[wildbill]

I think the problem was ---you were testing enfield's new proto type square line chain on a C5   

[Fragman]

I think the problem was ---you were testing enfield's new proto type square line chain on a C5   

Or I was using "hopeful laziness"& chain lube to make 'er last a while.
Cheers.

[Rattlebattle]

Jeez, I thought my chain was bad (actually it was). O ring it may have been but it had more tight spots than a leopard in a vice (ahem). It’s no wonder there was a lot of vibration. I took it to the scrappy.