Installing a Boyer Mark Four

Backtrack · Mar 7, 2018

Hi Folks...am new to Access, and Norton ownership, and have just got a new Boyer EI for my 73 850. I have removed the points and advance, as per directions, and both the Parts and Workshop manuals....so here is my question. The Allen key bolt supplied with the kit that hold on the rotor appear to be quite a bit too long, but the shop that sold the Boyer says they fit just right. Is this a case of cutting the bolt down, or am I missing out on a lot of thread on the end of the camshaft. Any help with this would be greatly appreciated. Thanks
Backtrack in BC

kommando · Mar 8, 2018

The bolt should not bottom out before locking the rotor so shorten it, but check first you are using
right bolt as they should have supplied a BSF and a UNF and they have different TPI's. Can't remember the correct one for the Norton but it may be BSF.

Esmerela · Mar 8, 2018

The kit is shipped with two bolts, 1 x BSF and 1 x UNF are you sure you are using the correct one ?

acotrel · Mar 8, 2018

From memory, one of the bolts supplied with the Boyer threads into the pick-up plate so you can release it from the taper at the end of the cam. The one that holds the pick-up plate to the cam is smaller in diameter.

L.A.B. · Mar 8, 2018

acotrel said:
From memory, one of the bolts supplied with the Boyer threads into the pick-up plate so you can release it from the taper at the end of the cam. The one that holds the pick-up plate to the cam is smaller in diameter.

I think you mean the Boyer "rotor" but the extractor bolt (5/16 UNF) isn't included.

http://www.boyerbransden.com/pdf/KIT00053.pdf

e) 1.25" x 0.25" BSF bolt & 1.25" x 0.25" UNF bolt

6) Fit magnetic rotor unit using one of the bolts (supplied),

Backtrack · Mar 8, 2018

Thanks to all that replied to my Boyer Mark 4 bolt /rotor install problem. You guys were right....the two Allen bolts supplied were different...and the second one I tried was a winner. Funny, I emailed Boyer about the same time as I posted my question here, and their reply was “cut the bolt down” WOW. Will consult this forum first next time before the manufacturer. Thanks again for the help.
Backtrack

Mr. Rick · Mar 8, 2018

...and their reply was “cut the bolt down”

Ouch!

Triton Thrasher · Mar 8, 2018

Backtrack said:
Funny, I emailed Boyer about the same time as I posted my question here, and their reply was “cut the bolt down” WOW. Will consult this forum first next time before the manufacturer. Thanks again for the help.
Backtrack

Sounds like Boyer were answering the question you asked, if your first post above is anything to go by.

Backtrack said:
The Allen key bolt supplied with the kit that hold on the rotor appear to be quite a bit too long

They may even have thought you had read the instructions quoted above, by LAB.

Fast Eddie · Mar 9, 2018

RTFM...

Tornado · Mar 9, 2018

I've a chance to buy a Boyer MK IV kit locally for good price, but it may be the 52 kit for Triumph/ BSA, not the 53 kit for Norton. Anyone know what is actually different? Mounting screws or something more substantial?

cliffa · Mar 10, 2018

Tornado said:
I've a chance to buy a Boyer MK IV kit locally for good price, but it may be the 52 kit for Triumph/ BSA, not the 53 kit for Norton. Anyone know what is actually different? Mounting screws or something more substantial?

Advance curve different ?

Maybe worth calling Boyer, they are very helpful normally.

L.A.B. · Mar 10, 2018

According to John Healy (Coventry Spares) in a similar thread on Britbike, the MkIII 'Norton' kit "is wired to fit directly on the motorcycle" otherwise they are the same so MKIV kits probably are too (as the MkIV '52' kit also contains the Norton BSF bolt).

http://www.britbike.com/forums/ubbthreads.php/topics/61431/boyer-for-a-norton-work-on-a-triumph

John Healy

The MKIII boxes themselves for the Triumph/BSA twin unit and the Norton are exactly the same.
What makes them different is the Norton, with its one application wiring, is wired to fit directly on the motorcycle.
The Triumph/BSA unit comes with generic wiring allowing it to fit all of the various Triumph/BSA twin applications (and the Norton if or when required).
John

http://www.boyerbransden.com/pdf/KIT00052.pdf

MK IV IGNITION SYSTEM FOR 12V TRIUMPH/BSA TWIN CYLINDER
.
1.25" x 0.25" BSF bolt (Norton)

acotrel · Mar 10, 2018

On a Triumph the Boyer rotor turns in the opposite direction to what it does on a Commando ? The setting-up instructions are probably different. In any case, I would always use the strobe light and degree disc to prove the timing is correct when the bike is running.

L.A.B. · Mar 10, 2018

acotrel said:
On a Triumph the Boyer rotor turns in the opposite direction to what it does on a Commando ?

Boyer rotors/pickups usually work in both directions using different timing holes (see Norton and Triumph instruction sheets). The rotor also turns in the opposite direction on Commando 20M3 models.

acotrel said:
The setting-up instructions are probably different.

Only due to the apparent differences between Triumphs and Nortons as John Healy says: "The Triumph/BSA unit comes with generic wiring allowing it to fit all of the various Triumph/BSA twin applications (and the Norton if or when required)."

Tornado · Mar 10, 2018

Sounds promising...have confirm the local kit is 52. Will reach out to B.B. To confirm compatibility with Nortons.
Thx.

Tornado · Mar 12, 2018

I heard back from Boyer technical support. They state Triumph, Norton kits have same electronics...and to just follow the Norton install pdf instead of included Triumph/BSA instructions.

The local kit for sale is new, unused and comes with new 6 volt coils...for $165 CDN, no tax/shipping. The same EI kit from Canadian suppliers runs $159 Cdn + shipping/taxes
Are 45 year old coils with less than 8500 miles, likely to need replacing anytime soon? Bike does run on them OK.
If coils are fine, I'll try to buy just the EI.

Craig · Mar 12, 2018

I would get the new coils as price is right ,and I would mount them along with the new Boyer .... very hard to tell condition of coils from looking unless obviously squeezed too tight at some point .... when I changed the old Boyer for the MKIV I got new coils at same time .... big improvement from setup that came to me ... make sure to run a dedicated ground from engine to battery while you are in there ..... ride season is getting close even over here on the Right Side of Canada , despite the 20 cams on ground now!

NortonMKIIA850 · Mar 12, 2018

Craig said:
I would get the new coils as price is right ,and I would mount them along with the new Boyer .... very hard to tell condition of coils from looking unless obviously squeezed too tight at some point .... [snip] ... make sure to run a dedicated ground from engine to battery while you are in there ..... ride season is getting close even over here on the Right Side of Canada , despite the 20 cams on ground now!

+1 – AFAIK the coils on my 44-year-old bike are original and they're still going strong, even though they've been squeezed too tight at some time in their life (I'm the bike's fifth owner) but a spare set of coils after all these years seems a good investment – spare coils can be useful in fault elimination besides being back-up. I think it would be important to try the new coils once you've got the Boyer up and running so that you know they work.

Tornado · Mar 14, 2018

After some more research. I found part numbers on the MKIV black boxes for Triumph and Norton are in fact different...at least per the sticker "BOX" numbers. Again, Boyer tech support replied to my follow email with both are the same electronics. No explanation for why the different box numbers and whether or not advance curves are different.
So I think I'll pass on the local deal for the Triumph kit52. Things are complicated enough on these machines without introducing more unknowns...

Installing a Boyer Mark Four

Backtrack

kommando

Esmerela

acotrel

L.A.B.

Moderator

Backtrack

Mr. Rick

Triton Thrasher

Fast Eddie

Tornado

cliffa

L.A.B.

Moderator

acotrel

L.A.B.

Moderator

Tornado

Tornado

Craig

NortonMKIIA850

Tornado

Similar threads