MPH conversion

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Walters
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MPH conversion

Post by Walters » Tue Jun 25, 2024 8:58 am

Hi

Apologies if this has been asked before but does anybody have any experience of KPH to MPH conversion, I have an 82 1100S that I have just imported from Italy.

I’m aware of the replacement faces but a bit concerned about damaging the clocks - also after doing this the true mileage will be distorted as the Odo distance originally in Kilometres will represent as Milage.

Any help or information will be greatly appreciated.

Many thanks.

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Uncle Bob
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Re: MPH conversion

Post by Uncle Bob » Wed Jun 26, 2024 10:12 am

I have several bikes with KPH clocks ( 250 and 400 Katana plus a Suzuki X7). In the past I've had 3 Italian 1100's and a TZR250 ( I won't count the Suzuki Gag bike!) and just left as kph and I didn't even bother with stickers. Never failed an MOT.

There aren't too many key numbers to remember (Ok a couple are near e.g. 50kph = 31.25mph)
50kph = 30mph
64kph = 40mph
80kph - 50mph
96kph = 60mph
110kph = 70mph

If you are good at maths in your head, divide by 8 and then times by 5!

I have noticed the kph clocks the 240kph (150mph) mark is about 12 oclock, but on the mph replacement faces I have seen, 150mph is nearer 1 oclock, so I'm not sure they are calibrated correct anyway.

Some have used the reduction converters that attach to the speedo but as you say, then the distance counter will be wrong plus you don't get the full sweep of the needle!

It's probably all personal preference, but you just get used to it.

As an aside possibly you don't need an MOT ( if it's old enough ) but if you do I have had one MOT place require a sticker on the headlight as it had the Italian light on it still, but another it always passed without. If you were going to change rather than get a UK Katana headlight I'd go for the MR2 mk2 crystal headlight conversion.

UB

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fossie
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Re: MPH conversion

Post by fossie » Wed Jun 26, 2024 9:13 pm

No issues with reasking a question my man .
Firstly as UB said why do you want to change it really , I ask because we have come across this issue before and a member had a MP/h face on a Km?h set of Italian clocks ..but they were widley inaccurate. The reason is the gearing in the speedo is calibrated to km/h so even with a Mp/h face on it will still point at where the km/h would be. Writing this it seems that is what you'd expect but it was miles out.
The most accurate method is the inline cable adapter, that changes the gearing .and the km/h readings are now mp/h...not expensive , but means you will only use the 6'oclock to 9 o'clock parts of the speedo.
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stockcar
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Re: MPH conversion

Post by stockcar » Thu Jun 27, 2024 8:05 pm

Or do what I did on one of the Italian stable’s finest and simply put 4x vinyl lines at the equivalent of 30, 50, 70 & 100mph…..
Having said that I drive a lot of varied JDM imports and often they are still in KM’s so you get very adept at doing mental maths :lol:

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Re: MPH conversion

Post by Walters » Sat Jul 20, 2024 2:50 pm

Thanks Guys

Guess I was hoping for a miracle when I figured you'd have to pull the clock apart to replace the faceplate, as the one on my bike is in fantastic condition, I'm gonna leave well alone & just put indicators the relevant speeds as suggested.

Including 20mph as I'm in Wales !!

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Re: MPH conversion

Post by Uncle Bob » Sat Jul 20, 2024 8:58 pm

Walters wrote:
Sat Jul 20, 2024 2:50 pm
Including 20mph as I'm in Wales !!
:lol:

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