Refurbished dynamo and other surprises

56G80S · Post by **56G80S** » Thu Nov 15, 2007 10:26 pm

My reworked dynamo arrived back from Tony Cooper. I'd had a real problem getting the thing back together with the JSL armature I'd bought. I seemed to have end float or be too tight. But Tony has done all for me, and keen to get out and sample the 6 volt halogen in all it's burning intensity, I set to work tonight.

But when I removed the chaincase I found that the DID primary chain had shed two rollers (adjacent to each other) and the Burman clutch centre had loosened. I'd been in a rush when I'd first re-assembled and found the Renolds primary chain after I'd put the DID one on and re-fitted the chaincase. As for the clutch nut I didn't have a box spanner or long socket to fit and as all were new (nut and lock washer) - those of a sensitive disposition and Alan look away now - I gently nipped it up with a hammer and chisel - the nut's hardly marked.

My problem is lining up the dynamo part of the engine sprocket with the dynamo sprocket. I just don't remember how. I haven't got a straight edge that'll fit in the gap and measuring off the back part of the chaincase is pointless, because it's not straight. I just use copius black sealant. No-one knows the difference and it doesn't leak (not from the joint anyway there's plenty of drips caused by other factors).

Tight twine won't fit the bill but experience tells me (how do you think the chaincase got bent) that if the chain runs aren't right there'll be problems. I've done it before, but can't remeber how! Did I write that before?

Suggestions welcome, except for those urging me to sell the 56G80S to someone who won't abuse it. I've just got the refurbished shiny black spare petrol tank back as well and can now get the original one done properly and it'll be another step towards the second machine (oops - don't tell Linda)

Johnny B

Merlin · Post by **Merlin** » Thu Nov 15, 2007 10:36 pm

Ref second bike just tell Linda what I told Marjorie,when I get it going I might sell the other bike,some chance of that

Biscuit · Post by **Biscuit** » Thu Nov 15, 2007 10:39 pm

The dynamo body should have a longtitudinal strip of metal that fits between the engine plates, that's why the rectangular cutouts exist around the dynamo cut out in the plates.

Easy enough to line up by eye.

56G80S · Post by **56G80S** » Thu Nov 15, 2007 11:13 pm

Alan, not with eyes like mine! Made up one of the locating strips, thanks to plan received from another Club member, but had to make the holes into slots because of my faulty manufacturing skills.

I'd planned to leave the cheesehead screws for the locating strip semi tight, line up the sprockets and then tighten the screws up then the dynamo strap.

What I could do is refit the primary chain and then carefully work off that to make sure the gap is consistent. Perhaps that's how I did it before.

Second machine has been a long term aspiration, I'd fancied something to take off road. Have bottom end, piston, no barrel, gearbox, tanks, mudgaurds. It's slow progress! Trying to match the year so that I get some interchangeability in the long run.

The off road sections of the Beamish Reliability Trial were a challenge, particularly when I did it the second time with a pillion. He promptly bought a large Yamaha and returned to biking. My, then, neighbour's wife didn't forgive me.

Johnny B

Don Madden · Post by **Don Madden** » Fri Nov 16, 2007 2:31 am

The strap is supposed to be slotted. Refer to the drawing I made & is now in the archives: technical/Do It Yourself parts/Dynamo strap.

As important as this alignment is, I would take pains to do it right. Remove the primary drive, inner & outer covers & slip the engine sprocket back on.

With the strap fixing screws just loose enough to shift the dyno, put on the chain & align the dyno to the engine sprocket. Then carefully remove the chain & dyno & tighten the screws.

Put the dyno & chain back in again to verify the alignment & when satisfied, put everything back together.

A bit of work, but you should only have to do it once & I would mark the position of the strap to the dyno in case it has to be changed again.

Cheers, Don.

56G80S · Post by **56G80S** » Sat Nov 17, 2007 11:27 pm

Don

Thanks for the advice. You'll have gathered that past experience means that I don't wish to skimp it!

I've made a scruffy job of the locating strip, but it does work.

Johnny B

Don Madden · Post by **Don Madden** » Sun Nov 18, 2007 12:00 am

Thas'sall right! I can't see it anyway!

Cheers, Don.

56G80S · Post by **56G80S** » Fri Nov 23, 2007 10:42 pm

Well, the clutch centre nut is nice and tight, thanks to the loan of a socket from patient garage that does my car. But I still have 0.015" rim rock on the clutch basket; suppose it's not much.

More important is that I seem to have a tight spot on the dynamo chain, which has had very little use and that was certainly not tight.

The shed has lost its attracttion for the night, so I'll check just how slack it gets if I adjust the chain at the tight spot. Maybe I'll halve the difference.

Bet that gets a reaction!

Any other suggestions?

Swear I didn't used to worry about all this stuff once upon a time. Even with the crankshaft sprocket and the dynamo sprocket nicely lined up, the long nut on the dynamo still seems very close to the primary chain, unless I take out the thick washer from underneath it. The woodruff key isn't fouling the washer, it stops short. Of course, if I do leave the washer out, there's not space to fit the lock washer and retaining clip.

I don't remember these problems or their solution. I get the feeling I've become a chronic fusspot.

Johnny B

laxy · Post by **laxy** » Sat Nov 24, 2007 9:01 pm

HI JOHN, If the dynamo chain has a tight spot then its only a cheap part to replace from the club or Surbeys.Remember this chain must be endless.What condition are the sprockets in? Worn sprockets knacker chains in no time.Please dont even think of fitting the sprocket retaining nut without the correct serated edge tab washer and the circlip that fits in the groove in the nut.Find a washer that, when the nut is tightened the tab washer just sits against the sprocket leaving just enough room to fit the circlip.You are right about the chains running close to each other.Probally why there is no spring clip on the dynamo chain.Very important to keep these chains tensioned properley you dont want them kissing when your out on the road.
Regards Keith

laxy · Post by **laxy** » Sat Nov 24, 2007 9:15 pm

Just remembered, from postings on this subject some time ago the dynamo is in the right position when the joint between the end cap and body is in line with the outer edge of the engine plate veiwed from above.When looking at other bikes at club night or rallies etc compare theirs with yours.