[SteveThackery]

I think that one would also be removing the fuel pump, and blanking off the large opening in the bottom of their fuel tank with cover that included mounting opening(s) for a petcock for gravity fuel feed. 

Yes, of course - I forgot about that and realised it while lying in bed last night!

[Crabsapper]

Yes, of course - I forgot about that and realised it while lying in bed last night!

I had mentioned it.

[Adrian II]

This is not trivial, especially since Hitchcocks seems to no longer offer the carb. retrofit kit.

They still list them for for older AND post 2017 EFI models as well as the Himalayan. 2nd row onward, although a 289 Amal might look quite good on a UCE... Interestingly, the Himalayan kit appears to have TPS.

https://accessories.hitchcocksmotorcycles.com/s.nl?ext=F&sc=1&category=&search=carburettor%20conversion

It's worth noting the H's early EFI to carb conversions DID feature an AVL-type alternator rotor and TCI, which upped the cost. For the more recent kits they found a way to keep the stock ECU to run as a plain TCI with the EFI rotor, so certain functions CAN be bypassed/spoofed or whatever without crippling the whole thing, also making it easier to revert to EFI for next owner preference or having to get through certain mandatory technical inspections.

A.

[Monkee]

I'm astonished by these stories of EFI failures. Are they actually real? Or are they stuff a mate said, or something you read on the Internet?

I've been riding for 50 years, and driving cars 48 years. I have literally never had a bike's electronics fail on me, and I've only had one electronic module fail in a car, and that was a good 35 years ago.*

They are extremely reliable, to the point where I don't worry in the slightest about them failing and leaving me stranded. If it happened, it would be pretty close to a once-in-a-lifetime event.

Oh, I've just remembered: a couple of years ago I had a reg-rec fail on a 40-year-old Yamaha - that had a carb, of course.

*I do appreciate that electronics were brought in part way through my 51 years.

I was riding with 2 other guys about 500km climbing up to the city which was at around 5000' MSL and the ECU on my bike quit it was a Kawasaki W800. Just the other month my mate's BMW R90 had a injector + fuel pump failure in the middle of a closed off and remote expressway that was under development. I guess i'm just unlucky or we had lemon bikes. But i'd rather not have to have that in the back of my mind enjoying my trip.

[Monkee]

They still list them for for older AND post 2017 EFI models as well as the Himalayan. 2nd row onward, although a 289 Amal might look quite good on a UCE... Interestingly, the Himalayan kit appears to have TPS.

https://accessories.hitchcocksmotorcycles.com/s.nl?ext=F&sc=1&category=&search=carburettor%20conversion

It's worth noting the H's early EFI to carb conversions DID feature an AVL-type alternator rotor and TCI, which upped the cost. For the more recent kits they found a way to keep the stock ECU to run as a plain TCI with the EFI rotor, so certain functions CAN be bypassed/spoofed or whatever without crippling the whole thing, also making it easier to revert to EFI for next owner preference or having to get through certain mandatory technical inspections.

A.

I was heavily considering H's kit but the cost for for the kit to get shipped and taxes after the fact was a little too steep for me it was more affordable and accessible to get the conversion parts form india and some local RE distributors here. As for mandatory technical inspections those are non existent in my neck of the woods and are frankly a joke if they said there was any thing of the sort. I have a technically road legal 2 stroke with no lights and puffs more smoke than a stressed out chain smoker.

[axman88]

They still list them for for older AND post 2017 EFI models as well as the Himalayan. 2nd row onward, although a 289 Amal might look quite good on a UCE... Interestingly, the Himalayan kit appears to have TPS.

Thanks for posting that.  I couldn't find them, but I was spelling carburetor the american way, with just one "t".

I see there IS one that is probably suitable for my '12 USA export  C5 after all:   https://accessories.hitchcocksmotorcycles.com/accessory-shop/Mikuni-Conversion-Kit-EFI-Models/38127

And I see I can source the flange adapter separately:  https://accessories.hitchcocksmotorcycles.com/Amal-Carburettors/Flange-Adapter-Straight/12667
and the Adaptor Plate:   https://accessories.hitchcocksmotorcycles.com/21879

Wow!  Glad I was wrong about these machined parts being discontinued.

Not that I don't like EFI, but it is one of those things that is great when it works, especially in my opinion, for winter starting, but a real bummer when something fails.   The only failure I've experienced personally, was due to a loose battery connection and very easily rectified.

But, to Monkee's point, it seems like if a major EFI component like the throttle body failed, I might find myself India shipping time away from a replacement part.  That's something like 4 - 6 weeks, IF the part comes at all.  If I was far afield, that could be a very expensive situation in both time and money.  It's not like a Honda Shadow or an HD, where, in the USA, one is never further than two days express delivery from somebody who has the part.    I guess I could rely on Hitchcocks, they are reliable and just a few days away.  My impression is that RENA can't be relied on to have UCE parts in stock.

This is why I pretty much view my C5 as a vehicle suitable for local travel only, no further than the moto rescue van is willing to travel.  Converting to a carburetor does seem to my mind, to reduce the number of unknowns and make MacGyvered solutions much more viable.  Does this seem reasonable, or am I misinterpreting the situation?

[SteveThackery]

This is why I pretty much view my C5 as a vehicle suitable for local travel only, no further than the moto rescue van is willing to travel.  Converting to a carburetor does seem to my mind, to reduce the number of unknowns and make MacGyvered solutions much more viable.  Does this seem reasonable, or am I misinterpreting the situation?

No, I think your conclusion is reasonable. Although I think modern electronics are very reliable, I also think that they are effectively irreparable when they do fail. In terms of sustainability, the carburettor is surely the way to go.

Now, about electronic ignition. Are you certain that you can find a system that's as reliable, or more so, than the original ECU? If reliability and repairability are of primary concern, you should probably revert to points-based ignition.

Realistically that wouldn't be practical, so you will need to carry a spare pickup and ignition module with you if you want the ability to repair by the roadside.  Are you willing to do that?

[Monkee]

No, I think your conclusion is reasonable. Although I think modern electronics are very reliable, I also think that they are effectively irreparable when they do fail. In terms of sustainability, the carburettor is surely the way to go.

Now, about electronic ignition. Are you certain that you can find a system that's as reliable, or more so, than the original ECU? If reliability and repairability are of primary concern, you should probably revert to points-based ignition.

Realistically that wouldn't be practical, so you will need to carry a spare pickup and ignition module with you if you want the ability to repair by the roadside.  Are you willing to do that?

Honestly if its at all possible I probably would. One of the reasons why i was thinking of getting a cone evo harley. I dont think there is a way to use condenser and points on the new UCE engines? if there are i'd like to know

[Adrian II]

I suppose you could come up with a clever mounting for a contact breaker assembly triggered by some sort of cam effort on the outer face of the rotor. Needs to be shaped so as to open the heel of the contact breaker fairly gently. Someone might already have done this, but I've never seen a report of it.

The AVL flywheel has a magnetic strip on it for the TCI trigger, I suppose you could do something with that.

You other option is to get an older style Bullet which already has points ignition.

A.

[axman88]

No, I think your conclusion is reasonable. Although I think modern electronics are very reliable, I also think that they are effectively irreparable when they do fail. In terms of sustainability, the carburettor is surely the way to go.

Now, about electronic ignition. Are you certain that you can find a system that's as reliable, or more so, than the original ECU? If reliability and repairability are of primary concern, you should probably revert to points-based ignition.

Realistically that wouldn't be practical, so you will need to carry a spare pickup and ignition module with you if you want the ability to repair by the roadside.  Are you willing to do that?

I don't see why carrying a spare ignition module would be objectionable.  It's small and inexpensive.  I'm not sure this is the correct one, but I would probably purchase a spare, right up front if I was making the conversion.  https://www.ebay.com/itm/195799258167

The pickup coil seems like there is little to go wrong, and might even be repairable with a bit of patience.  But again, small and cheap, so why not keep a spare?:  https://www.ebay.com/itm/295139818166

But, I don't think it would be necessary to carry.  It seems to me that an ignitor that would work adequately, although it might not be identical and would require hacking the wiring, could be pretty easily found in any number of motos from the 70s onward.  And there are all sorts of options on Amazon, just a day or two away.  Perhaps this one, from a Suzuki single, would be quite adequate to make sparks:   https://www.amazon.com/Amhousejoy-Motorcycle-Ignitor-Digital-Ignition/dp/B08B4S913J/ref=sr_1_2 

And my thought for self support while on tour, was not that I would carry everything I might possibly need, but rather that I would HAVE everything that MIGHT be needed, nicely organized, and if I ran into trouble, I'd call my friend back in Chicago, and have them overnight express me "box C-12", which I knew contained the part I had forseen might fail.  This same technique could certainly be applied to the original EFI system, but the cost of this advance planning becomes quite a bit higher, due to the longer list of more expensive components.

Sallying forth, without all this planning and relying on the basic reliability of the parts is probably fine.  Certainly people do it.  To Steve's point, these electronic components are very reliable.  On an HD, a Honda or a Yamaha cruiser, that sold well in this country, I wouldn't think twice about taking my chances, relying on the fact that spare parts were probably not going to be hard to find, if I had the very bad luck to experience a failure.  But, with the RE single, relatively rare in the USA, I would be surprised if a replacement for certain parts was NOT an issue.  I suspect that this isn't the case at all for the 650 twins, the 350s, and the Himalayans, but these are all in current production and mainstream distribution.

What we do, when we change from EFI to carburetor, the hard way, is to go from an electrical system that has 8 or 9 points of potential failure, (and substantially more if we count the wiring and connectors)
ECU
Fuel Pump
TPS
Pickup coil
MAPS (if equipped)
Temperature sensor
Lambda (02) sensor
Injector
Ignition Coil

To a system that has three.  This seems inherently more reliable.  I wouldn't be surprised if the most failure prone element of the electrical systems, are the connectors.  Less is better.
TCI
Pickup coil
Ignition Coil

I think it's valid to say that we will have given up some potential electrical failures for more potential mechanical failures in the carburetor, but the high pressure fuel system and its required regulator are unique to the EFI system.  In my opinion, mechanical failures are much more common than electronic, but are easier to fix. 

Declaring either as "more reliable" overall would be a complicated analysis.  I'd be going more for "more REPAIRABLE, with only parts from Walmart and working under a tree on a piece of cardboard", which is what I believe the mostly Indian proponents of "never EFI!" were also going for.  It took over a decade, and several emissions regulations updates, but that argument seems to have subsided.

Still, it does seem a little odd that carburetors on motorcycles may have survived longer in the new world, than in the old.
https://yamahamotorsports.com/models.php?product=259&action=features

[SteveThackery]

Still, it does seem a little odd that carburetors on motorcycles may have survived longer in the new world, than in the old.
https://yamahamotorsports.com/models.php?product=259&action=features

Perhaps I've misunderstood your point here, but I'll say it anyway...

Carburettors cannot meet European or American emission regulations, which is why every bike sold here has fuel injection (I seem to think bikes below 125cc are treated differently in the EU?).

Where emission regs are sufficiently lax, carbs can continue to be used. I think a carb plus a basic TCI will be cheaper than fuel injection.  I'm guessing bikes for the Indian market can still use carbs?

[SteveThackery]

I don't see why carrying a spare ignition module would be objectionable. 

No, me neither. I was just saying that if you distrust electronics for the very good reason that they are not repairable, then logically that should apply to the electronic ignition system as well. Hence pointing out you would need to carry a spare if you are hoping for a roadside repair.

Personally I'm happy to trust the electronics as they are. Perhaps I like to live dangerously, or perhaps my riding circumstances are much more benign. I suspect the latter. 

[Monkee]

I don't see why carrying a spare ignition module would be objectionable.  It's small and inexpensive.  I'm not sure this is the correct one, but I would probably purchase a spare, right up front if I was making the conversion.  https://www.ebay.com/itm/195799258167

The pickup coil seems like there is little to go wrong, and might even be repairable with a bit of patience.  But again, small and cheap, so why not keep a spare?:  https://www.ebay.com/itm/295139818166

But, I don't think it would be necessary to carry.  It seems to me that an ignitor that would work adequately, although it might not be identical and would require hacking the wiring, could be pretty easily found in any number of motos from the 70s onward.  And there are all sorts of options on Amazon, just a day or two away.  Perhaps this one, from a Suzuki single, would be quite adequate to make sparks:   https://www.amazon.com/Amhousejoy-Motorcycle-Ignitor-Digital-Ignition/dp/B08B4S913J/ref=sr_1_2 

And my thought for self support while on tour, was not that I would carry everything I might possibly need, but rather that I would HAVE everything that MIGHT be needed, nicely organized, and if I ran into trouble, I'd call my friend back in Chicago, and have them overnight express me "box C-12", which I knew contained the part I had forseen might fail.  This same technique could certainly be applied to the original EFI system, but the cost of this advance planning becomes quite a bit higher, due to the longer list of more expensive components.

Sallying forth, without all this planning and relying on the basic reliability of the parts is probably fine.  Certainly people do it.  To Steve's point, these electronic components are very reliable.  On an HD, a Honda or a Yamaha cruiser, that sold well in this country, I wouldn't think twice about taking my chances, relying on the fact that spare parts were probably not going to be hard to find, if I had the very bad luck to experience a failure.  But, with the RE single, relatively rare in the USA, I would be surprised if a replacement for certain parts was NOT an issue.  I suspect that this isn't the case at all for the 650 twins, the 350s, and the Himalayans, but these are all in current production and mainstream distribution.

What we do, when we change from EFI to carburetor, the hard way, is to go from an electrical system that has 8 or 9 points of potential failure, (and substantially more if we count the wiring and connectors)
ECU
Fuel Pump
TPS
Pickup coil
MAPS (if equipped)
Temperature sensor
Lambda (02) sensor
Injector
Ignition Coil

To a system that has three.  This seems inherently more reliable.  I wouldn't be surprised if the most failure prone element of the electrical systems, are the connectors.  Less is better.
TCI
Pickup coil
Ignition Coil

I think it's valid to say that we will have given up some potential electrical failures for more potential mechanical failures in the carburetor, but the high pressure fuel system and its required regulator are unique to the EFI system.  In my opinion, mechanical failures are much more common than electronic, but are easier to fix. 

Declaring either as "more reliable" overall would be a complicated analysis.  I'd be going more for "more REPAIRABLE, with only parts from Walmart and working under a tree on a piece of cardboard", which is what I believe the mostly Indian proponents of "never EFI!" were also going for.  It took over a decade, and several emissions regulations updates, but that argument seems to have subsided.

Still, it does seem a little odd that carburetors on motorcycles may have survived longer in the new world, than in the old.
https://yamahamotorsports.com/models.php?product=259&action=features

I whole heartedly agree with this sentiment. for me personally its not which is more reliable/better its whats easier to repair. IF i was going for a long enough ride and remote enough like i did a couple years back i definately would carry spares. Its never fun to push a bike up a hill for 5km.

[axman88]

Perhaps I've misunderstood your point here, but I'll say it anyway...

Carburettors cannot meet European or American emission regulations, which is why every bike sold here has fuel injection (I seem to think bikes below 125cc are treated differently in the EU?).

Where emission regs are sufficiently lax, carbs can continue to be used. I think a carb plus a basic TCI will be cheaper than fuel injection.  I'm guessing bikes for the Indian market can still use carbs?

I don't know WHY you say that.  There's no evidence that USA emissions standards are anywhere near as restrictive as Euro or Bharat Stage standards.

As you can see from that link I posted, Yamaha is still offering the carbureted XV250 in the USA market.  I'm quite sure I can find other examples of road bikes sold here that are carbureted.  The only reason that there are not MORE machines with carburetors, in my opinion, is because the USA is a small and shrinking market, and manufacturers choose to standardize their production to meet the demands of the largest markets.

As you can see HERE, the USA emissions standards haven't been changed since 2010:
https://www.transportpolicy.net/standard/us-motorcycles-emissions/

These standards have applied in the USA for the last 14 years:   HC+NOx   0.8 (g/km)    CO    12.0 (g/km)     NOx   n/a

These standards appear to me to be quite a bit LESS RESTRICTIVE than Euro 3 standards.  Which I find here:
  https://www.bikesure.co.uk/bikesureblog/2023/11/ulez-motorcycle-guide/#:~:text=Since%20then%2C%20the%20standards%20have,nitrogen%20oxide%20limit%20for%20diesel.

 HC+NOx   0.20  (g/km)    CO    2.3 (g/km)     NOx   0.15 (g/km)

Of course, by now, Europe is on Euro 5 standards for motos, and India skipped 5 and went straight to BS 6.  So, actually, you have it exactly backwards and India has the most restrictive standard for motos at this time.

[SteveThackery]

I'm happy to be corrected - thank you. 

My point remains: carburettors won't meet current emission regs (certainly here in Europe), which is why fuel injection is used nowadays.

I assumed the USA had similar standards to the EU, mostly because California led the way in emissions reduction, but if you say the standards are that much lower for bikes in the USA I stand corrected.

However, the fundamental principle remains: if carburettors are fitted then the emission regs must be lower than those in Europe.