Real Classic - - Contents -

Each ven­ture into the garage re­veals ‘In­victa’ in­scribed on the petrol tank of the lit­tle vet­eran – Latin for un­de­feated, un­con­quered. But is that mes­sage an en­cour­age­ment for PUB or a warn­ing from the 1914 2-speed belt driver?

Each ven­ture into the garage re­veals ‘In­victa’ in­scribed on the petrol tank of the lit­tle vet­eran – Latin for un­de­feated, un­con­quered. But is that mes­sage an en­cour­age­ment for PUB or a warn­ing from the 1914 2-speed belt driver?

The green shoots of nor­mal­ity are re­sum­ing. No, not the lift­ing of lock­down re­stric­tions but af­ter over a month of hot sunny weather, it is rain­ing out­side. At least it feels like Eng­land again. Ac­tu­ally the very slight lift­ing of re­stric­tions may per­mit a lit­tle rid­ing, al­though pos­si­bly still not rec­om­mended for us oldies? At any rate PUB has con­cluded that a short test ride to check out re­pair work can be added to shop­ping trips. Such rid­ing keeps her well away from oth­ers, and her pre­ferred short test routes re­main close enough to push home should a test not work out.

Cur­rently, how­ever, more bikes have been worked upon than tested – due, just as Frank said, to ‘dis­place­ment ac­tiv­ity’, ie. work­ing on what looks the eas­i­est task, un­til it stops be­ing the eas­i­est, in which case move on to the next eas­i­est. Of course, parts avail­abil­ity also in­ter­feres, but so far elec­tronic or­ders have come re­mark­ably quickly, save for a Big Port kick­start spring. No re­flec­tion upon the Aus­tralian sup­plier (who has a few other new vin­tage AJS parts avail­able), but pre­sum­ably in­ter­na­tional post is af­fected by border and flight con­trols. Nev­er­the­less af­ter over a month it seemed nec­es­sary to flag up ‘non de­liv­ery’ onto the eBay sys­tem. No doubt read­ers can guess what hap­pened next

– the par­cel ar­rived in the next morn­ing’s post. Oh dear, but an ac­knowl­edge­ment and apol­ogy was promptly sent, and the eBay pro­ce­dure ter­mi­nated.

The spring has now been fit­ted – ‘fit­ted’ in the old sense in part be­cause the not-quite-stan­dard fit­tings on the Big Port re­quired it be ‘ad­justed’ a bit. How­ever, that is one of the fixes yet to be tested. Ac­tiv­ity may have been a bit ‘scat­ter gun’, but this month the col­umn will con­tinue with the In­victa gear­box is­sue.

With lit­tle prospect of a Pi­o­neer Run this year, there was lit­tle ex­cuse for pro­cras­ti­nat­ing. But since when did PUB need any ex­cuse to pro­cras­ti­nate – it is a core skill? How­ever, the gear­box did need to come apart for in­ves­ti­ga­tion. A pho­to­copy about the Mk 4 ‘Jar­dine’ 2-speed gear­box from the Pre­vi­ous Owner pro­vided

a very help­ful di­a­gram of what was likely to be in­side, but al­most noth­ing about ac­tual main­te­nance or dis­man­tling in­for­ma­tion.

It is a cross­over gear­box like mod­ern Japanese items (or should one say that mod­ern Japanese gear­boxes are like the vet­eran Jar­dine?). With the big­ger of its bear­ings be­ing on the pul­ley side (off­side) it seemed likely that the in­ter­nals would come out that way. How­ever, the pul­ley is smooth and the ‘nut’ not hexag­o­nal. So first move was to saw and file the jaws of a re­dun­dant large span­ner to closely fit the only two flats. On the other side the sprocket was plain (ex­cept for the teeth), but at least with top gear se­lected (which just locks in­put and out­put shafts to­gether) a span­ner could be put on each side. Given enough heav­ing, one or other would surely come un­done.

It did, and it was the sprocket side. Us­ing a soft drift the sprocket came free be­fore too much force was needed, which, of course, is not good for the bear­ings in­side. To avoid that need in fu­ture, and to

fa­cil­i­tate lock­ing it, the sprocket was then drilled with plain and tapped holes. Three 3/8 BSF tapped holes were in­ter­spersed with three plain 3/8 holes, and whilst on the drill a fur­ther six ½ inch ‘light­en­ing’ holes were drilled just to make it look pretty (it lives un­der a cover so no-one can see it of course). A piece of scrap an­gle iron was drilled to match a cou­ple of the tapped holes en­abling the sprocket to be locked.

With the sprocket re­fit­ted, top se­lected again and the an­gle iron lock­ing it from ro­tat­ing, the far side pul­ley lock­nut could be at­tacked more firmly. It did not budge. Look­ing at the di­a­gram, and the belt pull, it seemed cer­tain that the pul­ley would be left hand thread and the lock­nut right hand. Noth­ing moved, even with the ap­pli­ca­tion of quite a big ham­mer. Just in case, the op­po­site hand was tried briefly, with­out any more joy. What next?

Some­times a re­ally tight nut re­sponds to be­ing ham­mered tighter, be­fore re­turn­ing to the cor­rect di­rec­tion, so PUB de­cided to ham­mer a bit harder the ‘wrong way’, then turn around and con­tinue the ‘right way’ again. How­ever, the fi­nal ‘wrong way tight­en­ing’ freed it and re­vealed that the lock­nut was in­deed left hand threaded. This is be­cause the pul­ley is not threaded at all but keyed to the shaft (ie. not as the Mk 4 di­a­gram). Nev­er­the­less it was un­done – and the di­a­gram now has ad­di­tional hand­writ­ten notes. The sprocket was un­done and re­moved again be­fore the gear­box was re­moved from the bike and onto to the bench.

The threaded bear­ing re­tain­ers came out eas­ily enough, and the bear­ings too, but not so the gear clus­ter. Pushed and pulled this way and that, noth­ing worked, and nei­ther did un­do­ing the gear se­lec­tor spin­dle – a mis­take that only com­pli­cated things. At times the in­nards were stuck, ap­par­ently un­able to come out, or to go in again. Tap­ping this way and that achieved get­ting the bits back in, but not out. Then sud­denly a tap had it all fall out rather ran­domly, but with no in­di­ca­tion of why or how, or, more im­por­tantly, how to put it to­gether again!

Even­tu­ally the trick was dis­cov­ered. The first pin­ion on the main­shaft is a tight and keyed fit on the main­shaft, but has to come free to al­low the shaft out, and that then pro­vides clear­ance to wrig­gle the rest free. All that is re­quired is a tubu­lar sup­ports for the slid­ing dog anda gears whilst the main­shaft is tapped free (al­though the dogs have to be aligned cor­rectly). Sim­i­larly, sup­port and tap­ping were re­quired for re­fit­ting (which was done a cou­ple of times whilst in­ves­ti­gat­ing the end float and se­lec­tor travel).

Things did not look too bad in­side, in that noth­ing was bro­ken, and there was only a mi­nor chip or two. Given the amount of harsh ac­tion the gear­box has to en­dure with no clutch, even be­fore bouts of drop­ping out of and into gear, it could have been worse. How­ever, the state of the dogs was less en­cour­ag­ing. PO (pre­vi­ous owner who, em­bar­rass­ingly, reads this col­umn) did get in touch to con­firm that yes, the gears

had re­cently been

re­placed, or cer­tainly at least three of them had, but not the main­shaft or slid­ing dog. So the slid­ing dogs, main­shaft dogs, and pos­si­bly the low gear pin­ion dogs, might all be over 100 years old – and they look it.

Ide­ally they would all be sent for ‘pulsed laser weld­ing’, a new process that PUB has just read about. This clever, mod­ern tech­nique can ap­ply suit­able met­als to hard­ened steel and cast iron with neg­li­gi­ble heat and there­fore no dis­tor­tion or de-tem­per­ing. The ar­ti­cle showed a pin­ion hav­ing a bro­ken off tooth slowly built up, and a gear­wheel so re­paired. PUB wants a ‘pulsed laser welder’!

How­ever, espe­cially dur­ing lock­down, a some­what sim­pler (and cheaper) so­lu­tion has been at­tempted us­ing a trusty Dremel tool. The gear­wheel and main­shaft dogs were eas­ily ac­ces­si­ble, and could be ground back a lit­tle to square them up, and as long as the parts are hard, which they seemed to be, that should work (case hard­en­ing is more prob­lem­atic ac­cord­ing to its depth).

The dou­ble-sided slid­ing dog is harder to deal with be­cause of ac­cess to the work­ing faces. It did oc­cur to PUB that one side (RHS in the di­a­gram) en­gages with the pul­ley spin­dle splines, sim­ply slid­ing along them, but never dis­en­gag­ing, so its dogs should re­main in good con­di­tion. Turn­ing the slid­ing dog around might be a good idea, al­though more gen­er­ally parts like to re­main paired up with those they have run in with, and such changes can be detri­men­tal. That should present bet­ter dogs to the low gear pin­ion, and the poorer ones to the splines they can­not dis­en­gage from. Clearly she is not the first to have this idea, be­cause the po­ten­tially good side also shows rounded dogs from a past life the other way around. Boo.

Nev­er­the­less, they were still the bet­ter side, so af­ter do­ing as much clean­ing / squar­ing with the Dremel as man­age­able, it was in­deed re­versed for re­assem­bly, pos­si­bly

back to orig­i­nal? It re­mains to be seen whether this is suf­fi­cient to dis­cour­age slid­ing out of gear. The bike is never go­ing to have to go for many thou­sands of miles, so if it works that will prob­a­bly do. If not, then ei­ther that new and clever weld­ing, or some re­made parts will be re­quired.

Hav­ing learned the se­cret of the one keye­don tight pin­ion, re­assem­bly was not dif­fi­cult, and with the sim­ple spe­cial tools it was soon re­fit­ted to the In­victa. Shop­ping trips were not suit­able for a clutch­less bike with neg­li­gi­ble car­ry­ing ca­pac­ity, so it has had just one short test ride. So far the re­sult seems en­cour­ag­ing, and the gears stayed put up the steep hill lead­ing to PUB Tow­ers – which the lit­tle In­victa plonked up with no trou­ble at all in low gear. Next time she might be brave and try again with­out the pre­vi­ously fit­ted ‘helper spring’, which should be in­struc­tive one way or the other.

With the vet­eran In­victa hope­fully OK, save that it may yet be re­turned to its orig­i­nal hand­change con­fig­u­ra­tion in­stead of cable and spring, thoughts turned to the vet­eran Tri­umph. This lan­guishes in the ‘shed of de­spair’ be­cause the run-and-jumps make it too dif­fi­cult for its aging rider. Back in 2016/17 she pre­pared for this day by buy­ing a mod­ern re­pro­duc­tion en­gine shaft clutch in the style of the pe­riod ‘Mabon’ ac­ces­sory.

When it ar­rived its taper did not match and it was so large and heavy that it was ban­ished out of sight to the back of a dark and lit­tle used cup­board. When the pain in the purse had faded, and rid­ing the Tri­umph got harder still, it was brought out and at­tacked with drill and lathe (see RC188 / 189). Thoughts have now turned back to try­ing it out, for which pur­pose it has been of­fered up.

It is still big, but per­haps not too big if it will work. The gear­ing on its overly large min­i­mum pul­ley set­ting looks daunt­ing, al­though no higher than she used to use many years ago, but can only be tested on the road. This re­quires the footrests to move back, and be wi­dened on that side by two inches, so suit­able lit­tle en­gine plates and a pegged spacer have been made up. There is still a clutch lever to ar­range, prefer­ably latch­ing like a cy­clemo­tor con­trol, and then a tick­over to con­sider. A sin­gle-speeder with­out clutch or neu­tral has never needed a tick­over ei­ther.

Maybe it will be rid­den again, or maybe all this is just ‘dis­place­ment ac­tiv­ity’, to avoid thoughts of sell­ing a val­ued old friend on which some amaz­ing trav­els and mem­o­ries were made – who knows?

Left: PO (pre­vi­ous owner) had found some Jar­dine in­for­ma­tion, which he help­fully sup­plied, in­clud­ing this di­a­gram. It was a sig­nif­i­cant as­set, but not 100% rep­re­sen­ta­tive of the In­victa’s gear­box

PUB’s home-made kick­start spring had proved a bit in­ad­e­quate, so she or­dered one all the way from Aus­tralia, which ap­peared to come by slow-boat. It went on with­out too much ‘fit­ting’, but has yet to be proven on ride outs

Left: This large ‘King Dick’ span­ner had been ly­ing around un­used for ages, so was at­tacked with saw and file un­til it fit­ted the pul­ley nut. It proved to be fairly tough steel, which is good, and the plain shank is ideal for us­ing it like a Vil­liers ‘ham­mer­tight’ span­ner

The pul­ley ‘nut’ is re­cessed, which makes it dif­fi­cult to ap­ply a span­ner squarely – espe­cially any kind of ad­justable. So the span­ner needed to be a good fit, and as it proved, suit­able for shock treat­ment (ie. ‘ham­mer­loose’) Three holes would pos­si­bly be ad­e­quate to pro­vide for an ex­trac­tor or lock­ing bar, but plain or tapped? So­lu­tion: three of each, then some big­ger ‘light­en­ing’ holes in­ter­spersed be­tween them. It would be quite pretty, if not cov­ered by a chain­guard The In­victa plain gear­box sprocket pro­vided lit­tle op­por­tu­nity for easy lock­ing (to undo nuts etc.) With the sprocket drilled it be­came easy to lock it us­ing this suit­ably drilled piece of an­gle iron

A Jar­dine gear­box in pieces, the in­ter­nals hav­ing fi­nally come out in a rather un­con­trolled way. Hope­fully re­assem­bly will be rea­son­ably log­i­cal The worst is over, and a re­assem­bly method and or­der found. Here the in­sides are back in­side, and just some fi­nal ‘but­ton­ing up’ needs do­ing POO ad­vised­did thath theh gears hhadd bbeen re­placedld withih new a lilit­tlel while­hil ago. MMore re­cent­lyl hhe iin­ti­mate­did that h maybe it was only three out of the four? If this is the fourth, and thus an old one, then 100 years of wear would ex­plain why the dogs are ta­pered not square (a newly made item should look bet­ter). The taper re­sults in dogs try­ing to push apart un­der load. Many mod­ern dogs are ‘un­der­cut’ with re­verse ta­pers to pull them to­gether – but this would not be ap­pli­ca­ble here be­cause of the dual duty of the mesh­ing slid­ing dog

The slid­ing dog is orig­i­nal, and shows con­sid­er­able round­ing from years of use, and harsh gearchange­s (there is no clutch). It was hoped that the other side would not show this wear, as it re­mains per­ma­nently en­gaged with the out­put shaft splines. But some pre­vi­ous owner had re­alised this and turned it around in the past – so now both sides are worn (and not easy to ac­cess) Hav­ing done the best to square up the in­ter­nal dogs that sim­ple home work­shop tools would al­low, the Jar­dine is here re­fit­ted to the In­victa. The poor photo an­gle is dic­tated by the lack of space in the garage to be 20% or more of the sur­vivors. Yes, the twoA very rare sight! Two In­vic­tas, which is reck­oned is a JAP with PUB, but not so the rear­most one, which stroke in front is the 1914 Vil­liers model now en­gined model of circa 1922

With one vet­eran hope­fully now fit to ride, at­ten­tion was turned to the vet­eran Tri­umph, which is fit enough but no longer man­age­able by its rider. The ‘Mabon’ style re­pro­duc­tion clutch, even in trimmed and light­ened form, would re­quire footrests two inches wider and fur­ther back. An ex­tra pegged spacer on the left, a longer bar (pre­vi­ous one shown be­low), and some lit­tle en­gine plates ap­peared to be the eas­i­est way to achieve this

The ‘Mabon’ style re­pro­duc­tion clutch ob­tained in 2016/17 had been ex­ten­sively trimmed and light­ened, and its taper re­cut to match the Tri­umph main­shaft. Here it is un­der­go­ing a trial fit, which is look­ing tol­er­a­ble al­though the large pul­ley di­am­e­ter still looks wor­ry­ing. The footrests are wi­dened and moved back a cou­ple of inches

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