The Marengo "Loki" Thread.

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Ah, that sweet smell of fresh air with a hint of perspiration.

It's all a matter of how fast you want to go.
I had no idea of the speed as there was no speedo attached. I have ordered one this morning. It will be here tomorrow.
 
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Who knew that fitting a ruddy Speedo could be such a pain in the bum?

As it is "Wireless" the sensor at the wheel needs to be within 60cm of the head unit. Clearly, the head unit is best placed right in front of you in full view.
The makers clearly expect you to be mounting the sensor on one of your front forks where the spoke-attached magnet can caress it with a magnetic field as the wheel rotates.
No front forks on a Tadpole, so I tried attaching a magnet to the disc-rotor and the sensor to a part of the steering arm. Just did not work reliably.
I tried mounting the sensor and magnet on the rear wheel, but then the head-unit could not connect to the sensor.
I struggled for ages to get the darn thing to work but all to no avail and I was feeling a bit miffed.

Luckily, the thing was only £9.99 so it could be "binned" without too much anguish and I wasn't going to shed tears over it.

However, I had a final try and found a combination that actually worked reliably.

The sensor is now attached to the 12mm x 3mm mudguard stay at the rear of the front offside wheel and the magnet doo-dad passes within the required distance. Bingo!

We have a working Speedo. :ROFLMAO:
 
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Update 14th May 2020:
Today I altered the gearing on LOKI by lowering it considerably.
I swapped the 18T rear sprocket for a 28T sprocket. Officially Nuvinci only support sprockets up to 22T, but what the heck.
This change has made the low-end highly effective although at the expense of the top end.
My aged knees and tired old muscles are appreciating the help though. 🤪



I think that instead of predominantly using the bottom 2 chain-rings (as I have been before this change); this gearing will mean I will be using the top 2 instead and the bottom 24T ring will be for fully-loaded pull-away's and severe inclines. It needs a fair bit of testing now. One issue I have found it that the standard derailleur mounting has the guide-wheel perilously close to the rear sprocket even at maximum adjustment, and vigourous back-pedaling can derail the chain. A bit of modification may be required.
 
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Update 14th May 2020:
Today I altered the gearing on LOKI by lowering it considerably.
I swapped the 18T rear sprocket for a 28T sprocket.
Well that 10 tooth difference means you still have quite a bit of wiggle room ?

This change has made the low-end highly effective although at the expense of the top end.
My aged knees and tired old muscles are appreciating the help though. 🤪
Top end is unnecessary if the main purpose of the trike to to enjoyed loaded touring.

I think that instead of predominantly using the bottom 2 chain-rings (as I have been before this change); this gearing will mean I will be using the top 2 instead and the bottom 24T ring will be for fully-loaded pull-away's and severe inclines.
I think what you should be aiming for is middle ring and Nuvinci in top a comfortable 10mph [ with full load ] at an easy cadence.

Then ride if differently to maybe you have in the past ?

So as above the ground will be level OK stay put.

Ground rises drop straight from middle ring to lower ring then the Nuvinci can be cranked down to low as needed.
Reason well it is easier to remember , usually hills quickly over power the small engine we are and as you have some over lapping gears you will still be comfortable ?

Normally you would drop down the Nuvinci to low , then when struggling as the hill still a challenge you have to drop the front ring AND move the Nuvinci towards top ? bit of a hand full when puffing and grinding ?

Ground rises either go straight to top ring [ if unloaded ] stay where you are if loaded ! there is no need for speed when touring with camping gear IMHO !


[/QUOTE]One issue I have found it that the standard derailleur mounting has the guide-wheel perilously close to the rear sprocket even at maximum adjustment, and vigourous back-pedaling can derail the chain. A bit of modification may be required.[/QUOTE]

Which adjustment is that you are using ? is this similar to the SA 8 problem you found ?
 
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Which adjustment is that you are using ? is this similar to the SA 8 problem you found ?
Almost but not quite. The derailleur mount is the one that came with the 26"-Wheels frame so is in the traditional and correct spot (I guess) and I have plenty of chain-wrap.
It is just that the mini-sprocket of the derailleur closest to the axle is virtually touching the teeth of the 28T rear sprocket.
It is because the natural action of a derailleur when at rest and in line with the sprocket is expecting a tiny 12T sprocket in that position not a 28T monster, when it climbs up a cassette to the lower gears it moves further out.
I have the "B" screw adjusted all the way to rotate the derailleur out from the rear sprocket and it just about clears it.
 
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I have the "B" screw adjusted all the way to rotate the derailleur out from the rear sprocket and it just about clears it.
Plan A:-
Ok then take the ' B' screw out and put a longer one in (y):D

Plan B:-
remove upper jockey wheel altogether and just use bottom one - your could use a really short cage one ?

Plan C:-
remove the derailleur altogether and fasten half of one somewhere else on the frame purely for taking the slack up
 
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Plan A:-
Ok then take the ' B' screw out and put a longer one in (y):D

Plan B:-
remove upper jockey wheel altogether and just use bottom one - your could use a really short cage one ?

Plan C:-
remove the derailleur altogether and fasten half of one somewhere else on the frame purely for taking the slack up
Yup, all of the above are definitely going to be tried in the order stated..... until a fix is found. I could really do with a long screw to be honest.
 
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Yup, all of the above are definitely going to be tried in the order stated..... until a fix is found. I could really do with a long screw to be honest.
Yup, all of the above are definitely going to be tried in the order stated..... until a fix is found. I could really do with a long screw to be honest.
And the winner is..... the slow comfortable screw up against the stop. Return derailleur-sprocket/cog now not catching on N380 drive sprocket.
 
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Update 29th May 2020:
I am glad to report that the changes to "LOKI" are now all completed and that I shall be calling it a "wrap". The gearing has been dropped so wonderfully low that even I can ride at a reasonable speed with no joint-distress.
So apart from any cosmetic "fixes" I am delighted with the modifications. It is non-e-assist at this time and will remain so until I desperately need the help. I have to say the it has turned out better than I had hoped and I actually prefer its simplicity over "Nicor". It is rock-solid and smooth as silk to ride. The steering is so good it even allows me to ride hands free on flat and level surfaces for short periods (until it hits a branch/twig/rock).
Very pleased with it and so I am calling time on this thread. Thanks for watching.:)
 
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Update 29th May 2020:
The steering is so good it even allows me to ride hands free on flat and level surfaces for short periods (until it hits a branch/twig/rock).
Doesn't that end in a buckled wheel ? ;):rolleyes:

Very pleased with it and so I am calling time on this thread. Thanks for watching.:)
What no updates for future travel/adventures ?
 
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