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Discussion Starter · #1 · (Edited)
Hi, I'm not far from completing my Les Harris T140 rebuild, but have come across a problem today :frown2:
One of the changes that I've made is I've removed the standard T140 exhaust camshaft 72-0025 for a 70-9989 exhaust camshaft.
My ignition system is a Lucas Rita AB11, and this afternoon I was re-fitting the part (? transducer) that locates and rotates in the camshaft, and it wouldn't fit. :surprise: I made an assumption that as the shoulder of the transducer was almost fitting into the camshafts hole that the new camshaft hole was a fraction undersize. So I put the transducer in the lathe and ground 0.020" off it in parallel as it originally was. Then I found that it was fitting further into the hole but still wouldn't go in more than half way...............then it dawned on me that the hole in my new camshaft was made for a taper fit, and not a straight fit as the transducer was and as my original camshaft also was designed for. (Also my original camshaft had a left hand threaded locating bolt as well).:surprise:
So I now have an undersize (where it locates) transducer and am now wondering if I've knackered the transducer for any future use. Does anybody know if I can buy a transducer for a Lucas Rita AB11 with a taper fit. I would have thought that the fittings would be the same, but it would appear not.
Could this have been designed this way just for the Les Harris Bonevilles?

Yours, a bit confused.
 

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Discussion Starter · #3 ·
You are correct, I mean the reluctor!

The reluctor on ebay is a different design to the one on my bike so I don't think it will work? My reluctor is essentially drum shaped with two raised ridges that run along the drum.

I've been wondering about just putting a new EI system now this issue has come to light but I was hoping to use the Lucas Rita.

Are all Lucas Rita reluctors "straight edged?"
 

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Dunno

That one looks like one from a 79
I have my old one somewhere. I can take a look

Alan Osborne who runs AO services repairs RITAS so he might be able to talk you through the differences

Stuart on here knows a fair bit about them as well.

Pazons are good (better?) and easy to install but if you can get Rita going for less than a tenner it has to be worth a go.

I can"t see the reluctor a being much different between T140's as the Harris bikes were pretty much the same as meridens afaik
 

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Hi Martin,

It would be helpful if you could post pictures of both the reluctor (side- and end-on) from your bike and also the fixed trigger unit in the old 'points' cavity.

Because Rita was originally sold for aftermarket fitment for years before being fitted oe, it fitted in place of points and auto-advance unit; as such, the reluctor had a taper to match that of the exhaust camshaft and the removed aau.

The Ebay reluctor that Dave has linked is specifically for the 5PU 'pick-up' (fixed trigger unit) used when Rita was fitted oe '79-on. I wasn't aware that the Co-op didn't taper the timing-side end of '79-on exhaust camshafts; however, I appreciate that you're talking about a post-Co-op Harris-built bike.

my original camshaft had a left hand threaded locating bolt as well
If correct, that would be Harris-peculiar; all Triumphs I've worked on had a normal right-hand thread into the end of the camshaft.

Regards,
 

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Showing my lack of knowledge- only ever really stripped triumphs and one CZ 2T

Aren't all camshaft/points arrangements tapered?

I know that some cams have a small key way and some don't but you need something to keep the relationship between the cam and timing device? I don't think that just a bolt done up tight is enough
 

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Just did a trawl and it does seem that the Harris used a different camshaft.
LPW list the part number as "parallel "
I assume to differentiate from tapered?

So you need a reluctor from an earlier Meriden T140?
 

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Discussion Starter · #8 · (Edited)
DaveM wrote; Aren't all camshaft/points arrangements tapered?

In my experience up until I stripped the LH T140, yes. But as this is the first Triumph twin that I have worked on for 25 years, I thought they must all be like that or if not, certainly the later ones. I never thought to ask when I was buying the camshaft, and the dealer who recommended the camshaft and sold it to me owns a LH T140, and so presumably never thought to discuss this point.

I have added photos of the "offending" items.





 

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That's completely different to mine!

I have the swoopy design (like two scimitar blades)
And the pickups are round plated steel with some black plastic(?) insulation

This seller
http://www.ebay.co.uk/itm/TRIUMPH-T...040613?hash=item5430722825:g:xUAAAOSw9eVXWcd2

Seems to be a reliable bloke and breaks loads of t140's
You could email him to contact you for a complete Rita from an earlier bike?

Personally I would fit a Pazon!

http://www.norbsa02.freeuk.com/goffypazon.htm

Goffy goes to kempton park dunno about other places.
 

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Hi Martin,

The pictures you've posted are of the 'standard' after-market Rita fixed trigger unit and a basically-standard after-market Rita reluctor; the only thing different is a 'standard' after-market Rita reluctor would be tapered to fit with the taper in the end of the camshaft.

If the new exhaust camshaft you fitted during the rebuild is tapered into the timing-side end, all you need is a "'standard' after-market Rita reluctor" for a parallel twin. :) Options:-

. as Dave posted earlier, try Al Osborn;

. if Al doesn't have any new, he'll likely be able to supply the data to taper the one you have, or taper it for you;

. look on Ebay for any after-market Rita for a parallel twin;

. worst case, just copy the taper on any Triumph aau?

. Only thing that isn't any use is http://www.ebay.co.uk/itm/NEW-LUCAS...RIUMPH-RELUCTOR-T140-BONNEVILLE-/221504438444. :(

Hth.

Regards,
 

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Hi Dave,

That's completely different to mine!
As I say, standard after-market Rita reluctor, apart from the 'parallel' mounting in the end of the camshaft.

I have the swoopy design (like two scimitar blades)
And the pickups are round plated steel with some black plastic(?) insulation
Lucas 5PU pick-up, as fitted just to '79-on Meriden twins.

http://www.ebay.co.uk/itm/TRIUMPH-T...040613?hash=item5430722825:g:xUAAAOSw9eVXWcd2
breaks loads of t140's
You could email him to contact you for a complete Rita from an earlier bike?
Why a "complete Rita"? :confused: All Martin needs is a reluctor.

I would fit a Pazon!
:eek: To paraphrase the well-known saying, that's a very expensive Fix for something that Ain't Broke. :)

Hth.

Regards,
 

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That's where my knowledge stops!

I wasn't sure if the box was also different. Or whether the harness would match between the '79 on and aftermarket /Harris
I was originally going to suggest the pickup and reluctor s/h

Pazon is about £100. For that you get a complete system with 7 year guarantee v a fix on a 30 year old one?
The box will still be old
I imagine any fix is likely to cost you £25-50 or time?
 

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Discussion Starter · #13 ·
Thanks for your assistance/information, Dave and Stuart.

I'll give Al Osborn a ring on Monday and see what he can offer, I won't bother him this weekend.
If he can't help, I'll try and find somebody to put the correct taper on the reluctor (although the distal end will now be undersize). This is beyond my abilities on a lathe.
If that proves too trying I'll go down the Pazon route probably.

As I bought this T140 as not having run for 18/20 years from my deceased friends widow, I can't actually be sure if the Rita actually works yet!

I appreciate your advice greatly, and I'll update with what happens.
Martin
 

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Do you have the Rita testing details?
It doesn't need to be on the bike to do some/all

I can look out my reluctor to measure the taper. Problem is I am no engineer, so can't guarantee the accuracy of what I do.

Does your camshaft have a "nib" inside' ?
That acts as a key way on some.
 

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Discussion Starter · #15 ·
DaveM wrote;Do you have the Rita testing details?
I've seen some Rita testing details on Al Osborn's website.

Does your camshaft have a "nib" inside' ?
Yes.

Regarding modifying the taper on my reluctor, I haven't ruled it out but it is unlikely that I'll get this done. I do know a really good engineer who could probably do the taper for me, but unfortunately he is having treatment for cancer at the moment so I don't want to trouble him.
 

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Hi Dave,

v a fix on a 30 year old one?
The box will still be old
I imagine any fix
:confused: What are we "fixing"? If Martin hadn't changed the camshaft, the reluctor that unbolted from it would've bolted back on it. He only has to get a new reluctor, or modify the one he has, because he changed a part entirely-unconnected from the Rita. Absolutely nothing has "Broke" on the Rita, so why would he "Fix It"?

Most bikes owned by contributors here are a lot older than "30". We do not replace them when they need a new part costing much less than £100, we buy the part. Yes, another, more expensive, part might break afterwards but ...

Same with a Rita. The reluctor is completely-separate from any other part. There is nothing to say an "old" Rita will go wrong, any more than an "old" crankshaft, conrod, piston, camshaft, gearbox, yadda, yadda will go wrong. In fact, being electronics, an "old" Rita is far less likely to go wrong than an "old" crankshaft, conrod, piston, camshaft, gearbox, yadda, yadda - they're mechanical and wear, electronics don't; assuming no well-meaning-but-incompetent-amateur, the usual adage is "the longer they go on, the longer they go on". :)

Pazon is about £100. For that you get a complete system with 7 year guarantee
I imagine any fix is likely to cost you £25-50 or time?
The Rita on my first triple (and likely the one on the second one too) was older than 7 years when Martin's bike was new; both Ritas on my bikes are still going strong.

Any "guarantee" is only of any use when the thing goes wrong. Even at "£25-50", fixing something that actually goes wrong with the Rita will still be "quarter-half" the price of the Pazon; "time" will be expended whether it's sending the Rita to Al Osborn (in GB, no customs, same as Martin) or the Pazon to New Zealand (half-way around the world, customs, etc.).

Worst-case, even if Martin ever has to shell out for a Pazon because the Rita box is irrepairable, the Rita reluctor and trigger unit have a value on Ebay. :thumb

Hth. :)

Regards,
 

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Hi Martin,

I've seen some Rita testing details on Al Osborn's website.
Where are you exactly with needing the Rita?

Are all the bike's electrics connected and ready to go? If so, I can detail how to test the Rita.

Otoh, if the electrics aren't ready to go, when you 'phone Al (Osborn) about the reluctor, ask how much he'd charge to test it? Ime, it'll be minimal; Al has a rig to simply plug in all or parts (box, trigger unit and/or coil(s)), when the bits can be run up; it literally takes minutes.

Having worked on numerous e.i. since I achieved Guru status in the early 1980's ("In the realm of the blind, the one-eyed man is king" :D), the number of actually-failed Rita boxes I've come across I can count on the fingers of one hand and have fingers spare (the Meriden-fitted 5PU pick-up is ... uh ... less reliable ... :().

Otoh, I have no experience that suggests it's wise to advise you to blow £100 on a Pazon based purely on the age of an untested Rita.

Hth.

Regards,
 

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Discussion Starter · #19 ·
Hi Stuart & Dave, I rang Al Osborn yesterday and he has only one suitable reluctor that will fit my bike in his stock (which I think IIRC has a transducer to make a working unit) and so is reluctant to sell it to me.
But he has several "Harris type parallel" reluctors in his possession and has/is trying to get someone to turn these down into a taper to fit the earlier "Meriden" exhaust camshafts.
He is going to contact me next week about any progress regarding the modifying of the reluctors. To be honest, I'm not too hopeful based on what he said, but who knows, maybe he'll come up with the goods?

StuartMac wrote;if the electrics aren't ready to go,
The electrics including the AB11 box are all fixed onto the Triumph so not easy to send off.

I considered writing to Trijub750 regarding this, but based on what I've found out, all "Meriden" versions will have the "S" styled reluctor, and so haven't.

We'll see what next week brings, but a Pazon is starting to look like a highly likely purchase.
 

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I have fished out my reluctor, S type.
problem is that i only have a digital vernier, and the point end seems hard to measure.
I might be able to get an engineer to measure it for me.

I will email somebody
 
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