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Member postings for Alan Donovan

Here is a list of all the postings Alan Donovan has made in our forums. Click on a thread name to jump to the thread.

Thread: Garmin sat nav
18/07/2021 06:32:27

Hello all.

Note to Clive Foster, You may be able to update your Nuvi with all of Europe again.

I suffered from being unable to update my Europe map on my Nuvi. The best I could achieve was the Benelux countries & France (without the UK). But my Nuvi is able to have additional memory installed (up to 32Mb on a micro SD card).  Memory was about £12 at our local supermarket. There is a memory slot at one end of the Nuvi body.

The memory was installed, the Garmin update programme recognised this, and now have Europe and the UK maps back on the device.

Hope this helps.


Edited By Alan Donovan on 18/07/2021 06:35:24

Thread: Shock at low pay for high skill
11/07/2021 21:52:04


I have been following most of this discussion, and Bazyle made a couple of interesting comments.

In my years as an Engineer, the ability to use higher mathematics (Algebra) was necessary. I cannot see how an engineering designer can design a piece of equipment if he cannot prove to himself and more importantly the client that it is 'fit for purpose'. There were times where an even 'higher' level of mathematical skill was required and we had a 'Stress Office' to provide guidance to the designer and/or fulfil that function.

The main problem I saw was not the ability to perform mathematics but the ability to actually understand how a component or structure is loaded when in use. Not all loadings are the 'text book' example we may think they are.

Degrees are regarded by industry as essential, but many of the degree qualified engineers are unprepared for industry. This is NOT a criticism of the graduate engineer, but a criticism of some (not all) employers who expect graduates to know ALL the answers. Some gentle mentoring of a new graduate by an experienced colleague(s) can make such a difference to the graduate AND the success of that company.

Do employers check that their employees have the qualifications (Degrees) they claim?

I would hope so and as part of the company's Quality Accreditation they are supposed to 'back check' with the issuing University (who should provide 'hard copy' evidence/proof). For large contracts, the CVs of those 'highlighted' to be working on the project are (usually) included in the bidding documents. Well ..... they were at one company I worked for.

I do however share Bazyle's concerns about whether employers make sufficient checks about a persons qualifications. But that is where the Auditors for the company's Quality Accreditation Organisation verify that the company is maintaining the necessary quality processes to retain their accreditation.


Thread: De-snagging an SL125
27/06/2021 15:43:03

Hi all.

Thank you so much for all your input. There are plenty of options for me to try. I have provided a sectional sketch of the outlet end of the muffler below.

I have found a piece of pipe in my 'it may come in useful one day' pile that is a snug fit on the exhaust (diameter A). So first off, I intend to start with just a short extension tube and see what effect that has. I could then try and add some sound insulation on the inside of that and see what effect that has if still noisy. - basically as per Phil P's suggestion.

I will probably try the diffuser style of modification as well just to see how that compares to 'tail pipe' mod.

To answer Emgee's question the diffuser would have a closed end according to the diagram, but my thoughs are to push the diffuser against against the baffle therefore effectively closing off the end.

I will try the easy solutions first before moving on to the more difficult stuff.


Best regards.


27/06/2021 08:59:09

Hello again

Thank you all for your comments so far.

The outlet on the aftermarket muffler is smaller than the inlet pipe. The actual exhaust pipe is the inner pipe in the photo below.



The inner pipe is welded into the muffler and has a baffle at the end of it. I think this is supposed to emulate the OEM diffuser, but as you comment the baffle does not appear to be doing much. There is a reasonable gap between the end of the inner pipe and the baffle, so I think it is worth making a diffuser to suit this. As mentioned earlier this pipe is smaller than the inlet end, so If this combined reduction in the 'gas flow area' is detrimental to the bikes performance, then that is the time to consider modify the outlet further.

P.S. Just a thought while writing this. The black box on the exhaust system is described as a 'muffler'. Is a muffler an alternative term for silencer or is a muffler technically different to a silencer?

Best regards to all.


Edited By Alan Donovan on 27/06/2021 09:01:39

26/06/2021 21:42:55

Hi John.

In answer to your question, I don't know.

My son and I bought this as five boxes of bits. Even the engine was down to its component parts. So we never heard it running.

It does seem to attract a lot of attention when I am riding it, and my neighbours say it is loud.

It is an all welded unit, and it doesn't feel (?) as though it has any packing inside - I may have to have a 'prod' inside to see its there is anything 'spongy' there.  

The muffler was bought new, by us, as the old one wasn't present when we bought the bike, but it is an aftermarket unit, which I am positive isn't built / manufactured to the same standard as the OEM equipment (for this particular item).


Edited By Alan Donovan on 26/06/2021 21:44:33

Edited By Alan Donovan on 26/06/2021 21:47:38

Edited By Alan Donovan on 26/06/2021 21:53:24

26/06/2021 21:21:03

Hello all.

For those of you that have been following the challenges of renovating a Honda SL125, it is now running, on the road, insured and officially an 'historic vehicle'. I am currently 'de-snagging' the vehicle.

A current 'snag' is that the exhaust is (very) loud.

It has an aftermarket muffler which isn't as well engineered (or expensive as an OEM unit - $2999.95 U.S.) but has the correct contours and is aesthetically correct. I propose to modify the aftermarket unit by putting a diffuser in the exhaust stream to hopefully deaden / reduce the sound. I propose that the diffuser will be similar to the OEM design - see item 6 on the sketch below.


This would require removing the existing outlet pipe and an internal baffle (Rotabroach cutter maybe) to provide room for the diffuser.

I am relatively confident I could make a diffuser to suit from steel, and that the primary design parameter is that the diffusers combined 'flow gas' area should be not less than the open cross sectional area of the current exhaust outlet.

So my queries are -

Is the above design parameter reasonable and do you think a quieter exhaust note would result?

Are there any other issues I should take into consideration?

Should I leave things as they are and claim ' historic vehicle / old technology' if challenged?

Lastly, and this is the most interesting bit,- have any of you any different solutions that could be applied to this to result in a quieter exhaust.

All the best, and thank you in advance for any input / comments


Thread: Taper due to tailstock height misalignment.
04/06/2021 11:28:07

Hello All.

My experience is that having a 'high' tailstock is not unusual for a conventional lathe.

I served my engineering apprenticeship (late 60s/early 70s) at a machine tool company, where it was accepted that tailstocks could be a little 'high'. My memory is vague on this but I think 0.001 inches was the maximum allowable compared to the headstock.

The logic behind this was that as the tailstock would be moved around with use, the tailstock base would wear (headstocks being fixed), so the tailstock would gradually drop to be on dead centre height with the headstock before becoming 'low'. This therefore extended the time the vertical relationship between headstone and tailstock remained accurate.


Thread: Boxford paint colour - but not blue or green!
31/05/2021 10:56:29


I have had to match paints a couple of times and the more specialist paint suppliers now have a hand held device that can 'read' the colour and give you the shade and/or RAL number. It literally only takes a minute or two.

The first occasion I needed this service, I used one of the larger (but local) glazing companies. They often need to colour match paint to paint the reverse side of windows or glass splash backs. So that is another route to what you want.

I have no idea how these devices work, but I assume that you would have to get the painted sample as clean as you can before getting it scanned.

Hope this is useful. Alan.

Thread: Myford ML7 headstock belt length
28/04/2021 18:03:47

Hi Rob.

My ML7 manual quotes the belt length as 23 inches, inside length.

Best regards.


Thread: Care home fees and what they want.'
28/04/2021 11:07:18

Good morning Peter.

Their information request seems exceptionally intrusive. The suggestion to seek some legal advice with respect to this issue is probably very good advice.

One issue that sprang immediately to mind is – has your mother left any money/possessions to you, siblings and/or grandchildren ‘In Trust’ or in her Will. It may be worth taking legal advice to ensure your mother’s wishes are adequately protected.

When seeking a placement for my father-in-law (diagnosed with dementia) we found social services very unhelpful. So to do ‘the best’ for my father-in-law, my wife and I had to become experts in the care system. This occurred in 2012 so my comments and experiences may not be quite so relevant now.

We found organisations such as quite useful, one of these organisations offers (or offered at the time) free legal advice. You have a limited time (30 minutes) to talk to the solicitor so be well prepared with your questions.

One ‘gem of information’ that came out of my conversation with that solicitor was that Care Home ‘Top-up fees’ (which are usually paid by relatives) are NOT compulsory. The phrase ‘emotional blackmail’ comes to mind here.

We didn’t pay any top-up fees (although they tried a second time to force the issue after my father-in-law was resident in the home), but we have had sight of a ‘Top-up fee’ agreement. If you choose to pay top-up fees, read the document very carefully, and make sure you understand the T&Cs – our experience is there is NO escaping the payments once you have signed – regardless of how your personal situation may change.

Lastly, if your mother is self-funding, may I suggest you keep control of when payments are made. My (ex)neighbour put her trust in her father’s care home to manage the self-funding payments as required and then later found that the payments made were in excess of the contracted amount. The excess fees were returned ......... eventually.

I accept that good care has a significant price tag attached to it, but the Care Home business is exactly that - a business, so unfortunately, in some organisations the ‘quality care/profit’ balance has become far too ‘profit orientated’.

I hope this has been helpful to you.

All the best to you at this difficult time.


Edited By Alan Donovan on 28/04/2021 11:17:25

Thread: Honda SL125 timing - SANITY CHECK.
12/04/2021 14:35:23

Hello again.

Thank you all for the responses to my question. It is very much appreciated.

Best regards to all and keep safe.


Thread: Cleaning a tacho glass
12/04/2021 14:30:21

Hi Hopper.

I did think it was a long shot, and that the use of a solvent was a non-starter, but I thought I would ask the question anyway.

I hadn't considered condensation as a possible cause rather than a soaking, but the reality is that although it 'works' I have no means of checking if it is accurate. I will probably just leave it 'as is' for the immediate future.

Thanks for your input.


12/04/2021 11:54:02

Hi all.

This may be a 'long shot'

I have a Honda (circa 1975) motorcycle tachometer which is dirty on the inside of the glass (which I would assume to be plastic). I looks like the tacho has had dirty water inside at some point. The unit appears to be of 'snap together' construction as there does not appear to be an obvious way to remove the glass. I would like to preserve the original part as it is, if I can, as it is still working.

Has anyone any experience of successfully cleaning the inside of a tacho glass using a non-aggressive method?

Initial thoughts are carefully pouring a suitable solvent (rather than soapy water) into the unit, through the hole for the night time illumination bulb, avoiding the tacho mechanism, and gently swilling around to remove the dirt. Has anyone any experience of this? Did it work?

It's not a big hinderance to leave it dirty, it is still readable - but it would be nice to have a clean glass.


All the best & thank you.


Edited By Alan Donovan on 12/04/2021 11:56:29

Edited By Alan Donovan on 12/04/2021 11:59:14

Thread: Honda SL125 timing - SANITY CHECK.
12/04/2021 10:43:25

Hello all.

May I have a 'sanity check' please!

From my last post on the Honda (re electrics), I mentioned that my timing may be 'out'. I have since checked the timing by two methods (instructions in the manual using feeler gauges and the T and F timing marks on the rotor, and a method using a multimeter) and both say it is OK.

A subsequent check using a timing strobe 'suggests' it is way out - but I have now come to the conclusion that the instruction manual is a little ambiguous. The manual instruction (5) says when using a timing light ............ The two marks on the rotor should swing around and line up with the pointer when the engine is revved.

What the manual doesn't say is that it is specifically referring to the two marks WITHOUT the T and F annotation. If it is referring to these unannotated marks then my timing is correct using the strobe light.

Have I now interpreted that correctly?

Please find the relevant extracts from the manual below.



Best regards & many thanks.


Thread: Honda 125 electrics
02/04/2021 18:38:44

Hi All.

Here is some feedback on the Honda SL125.

Checked and cleaned the earths, and ran some extra earth wires from the indicators (belt & braces). Started the SL125's engine and made the light/indicator checks with engine running.

With the engine running you are able to have both indicators and the headlamp on (as suggested by a few of you), but I did note that even with the engine running the headlamp did 'dim' a little as they came on. Also the indicator flash rate seemed OK to me. From the consensus of opinion on 'vintage Honda electrical technology' I am happy with the result.

The timing is not quite right (according to the strobe), so that is tomorrows project all being well.

Many thanks to everyone with their views and advice. Keep safe.

All the best. Alan.

29/03/2021 18:15:37

Hi All.

Thank you all for your advice and guidance.

I will check the system out with the engine running and also check out or provide new earth connections. It seems to be the general opinion that 6 volt systems are pretty poor and I should not expect too much of an improvement unless I change to 12 volt system. Thinking back to my Lambretta days (late 60s), I seem to remember that had a 6 volt system and that was not brilliant. 12 volt conversions were 'all the rage' then.

With respect to the availability of spares, I did manage to buy a number of spare bulbs and plugs of the correct specification via the on-line auction house.

Tim Stevens - you have certainly given me an alternative option and I shall not discount converting to a 12 volt system.

Best regards to all. Alan.

28/03/2021 20:23:45


Thank you all so much for your input, I really appreciate your help.

I will try the lights with the engine running first, as that is an easy thing to do. Regardless of the result, it may be worth checking the cleanliness of the 'earth paths' anyway, as the bike is still a 'work in progress', and I wish the bike to be in the best condition for road use.

From the comments so far I have plenty to consider, and I will be so much wiser (I hope) about motorcycle electrical systems.

All the best and thank you all.


28/03/2021 17:24:10

Hello all.

I am coming to the latter stages of restoring a 1975 Honda SL125.

The original indicators were beyond being salvaged and have been replaced with aftermarket parts. All electrical connections have been made. The bike has a 6 volt battery and 6 volt electrical system as per original design.

The bike has a new battery and it is fully charged. With the battery in this condition the indicators work as I would expect. Bright lights with a respectable flash rate. With the battery half charged the lights appear a little 'sluggish' to illuminate and the flash rate seems slower. Also, in both scenarios, the neutral indicator light dims when the indicator flashes. I would expect this to be normal performance - but I am happy to be corrected on this.

This is where it goes further astray.

The problem is when I switch on the headlight this seems to 'suck' the power from the battery such that the indicators are feeble to none-existent. The indicator circuit is getting something as the the headlight dims in unison with the indicator relay. I assume this is not normal performance and that the indicators and headlamps should perform together as needed.

May I ask for suggestions as to what may be the cause of this, and how it may be corrected.

I have not check this out with the engine running - if that is relevant.

Apologies for the 'long ramble' but I am trying to give as much information to you as possible.

Many thanks in advance to anybody who responds.

Best regards. Alan.

Thread: New member
09/02/2021 18:19:34

Sorry to heard about your problems.

First off, did you have the lathe actually running when you friend switched on the Milling machine. If so maybe it’s a simple case of a blown fuse somewhere due to an overloaded circuit. I assume you have already checked this, but I feel it is worth reminding ourselves of the basics. Is there the possibility that there is a second fuse in the circuit? Just a thought.

Secondly, have you spoken to the previous owner/user, maybe he can offer advise as (I assume) he was the installer of the equipment.

Best of luck and I hope you are ’up and running’ very shortly.

Lastly - welcome to the forum.


Thread: 00 Gauge Live Steam Locomotives
04/02/2021 07:49:19

Hi James.

I cannot help with your original question, but there is a society for those interested in these models.

This may be a good place to start.

Best regards & keep safe. Alan

PS.  Please report back what you find as I am sure others will be interested. 

Edited By Alan Donovan on 04/02/2021 07:51:50

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