BT-H Mag

[Monkeypants]

I have D ingition on one Rapide and Norton dual point dual coil on the other. Both work well but the Norton dual point setup provides a hotter spark at slow kickover.

The bike with the Norton setup can be started easily while seated, it's just a case of dropping the right leg. At the 2007 IOM Rally Colin Dunbar stood on the left side of the bike when I started it. He thought it had an electric start because of the lack of starting effort required.
Don't know whether it's due to the ignition or not, but this bike (about US. Shadow spec) also goes very well. It has more go than the other Rapide which is all done out with Lightning cams, two front heads, big carbs and high compression.

The only problem I have encountered with the Norton point ignition in 24,000 miles occurred when I decided to spruce up the ancient Lucas points with some expensive new Japanese points supplied by British/Italian MCs in vancouver.
The heels on the Japanese points were so soft that the point gaps narrowed from 25 thou on installation to 15 thou after 500 miles. I found out the hard way that with this setup a wide gap must be maintained or the spark to the rear cylinder dies out.

After the problems with the Japanese points I located several sets of NOS Lucas points and now have enough on hand to do a million miles or so! I've been told that the original Lucas points could last up to 60,000 miles with just a bit of cleaning now and then.

Glen

 

[bmetcalf]

How about an Egli report?

 

[Monkeypants]

Not much progress, I'm waiting on a new TIG welder that should be here next week.

I did order the crankcases this AM. After much deliberation, they are being supplied by Andy Molnar. He will also do the mods for Terry's oversized oversized mainbearings , 30mm id, 72mm od and bore out the cases for the 92 mm liners. I might use Norton Commando Superblends for the roller bearings, they will fit.

I considered using Magnesium cases which were offered, then retracted by Patrick Godet. After severals emails back and forth quoting prices and some trumpeting about the quality of his stuff, which I know is good, he decided he would not sell cases to me as his technology is reserved for "Customers" I guess 7k$ for cases and covers does not make one a customer!
Anyway, it seemed he was very much into selling me the cases until I sent him a photo of the bike , and then it was "you must not have my technology"
Surely he understands that I would use it for the good of mankind rather than evil!

After more reading about Magnesium cases and some advice NOT to use Magnesium, I decided to use Aluminium.
I thought that if anyone should be casting Vincent cases in MG it would be Andy Molnar, given the amount of experience he has in building his Magnesium Molnar Manx engines. He feels that the Vincent case is not a good candidate for casting in Mg and that it needs more webbing and thicker sections (like a Manx case) in order to survive high RPM or hard usage if cast in Mg.
This begs the question of why bother, if a good deal of the weight saving by switching to Mg goes back into the need for thicker material and more webbing?

After the first bit of advice NOT to use Mg, I thought, why would there be a problem, all of the VW bugs used Mg crankcases.
Some reading on that topic showed that the MG cases were OK on the old 36 hp and under bugs, but as soon as slightly more powerful versions (40hp-60 hp) were built, problems showed up in the Mg cases. Volkswagen went to higher and higher percentages of Aluminium until the ended up with an alloy that is not much different than a standard Vincent case.
These aluminum Volkswagen cases are the ones that hotrodders look for when building a racing Volks motor.

So the finished weight of the bike is back to a hopeful 360, still 20 or 30 pounds lighter than a new GSXR.

I have also ordered a Newby belt drive setup in a ratio that he is offering for the first time in a double toothed version, in fact he has the belts for this setup on order but has not received the first one yet.
This is a 1.66 primary ratio, so quite close to the stock 1.6 Vincent ratio. In the past he could only do the 1.66 ratio for a racing bike without dynamo drive(single toothed belt)
He also has one other new product for use with large capacity Vincent engines, that is a 7 plate clutch. Prior to this his standard clutch was a four plate and the heavy duty version was 5 plate. The new clutch is the same overall width, the plates are thinner.

Glen

 

[CarlHungness]

B-TH MAG Problem

Hi:
I could not give the B-TH magneto a higher recommendation, most especially when compared to a stock, rebuilt magneto. I have covered over 50,000 miles with my B-TH and literally from the moment I started the bike with the unit on, I liked it. Starting the machine is now a piece of cake, it starts on either cylinder, although I do like to try and find the rear cylinder just for practice. The machine ticks over very nicely with some stock 289 carbs. My only complaint, and it is most likely not the mag's fault, is that my mag cowl may very well be "rich" in casting and although I have removed lots of material in anger, I still cannot get the cowl to sit as flat as it did with the stock unit as it fouls the coils.
As far as swapping it for the fine series D battery powered unit, there is no possibility that will happen in my case. I absolutely love the idea of being able to start the bike with no battery at all. In fact I did remove the great McDouglator in Minnesota a couple of years ago after a parking lot transmission rebuild, and simply rode the bike home with no generator.
Since reading of the problem on this thread, I may consider buying a couple of extra coils and carrying them on trips.
Best,
Carl Hungness

 

[BigEd]

Hi:
I could not give the B-TH magneto a higher recommendation, most especially when compared to a stock, rebuilt magneto. I have covered over 50,000 miles with my B-TH and literally from the moment I started the bike with the unit on, I liked it. Starting the machine is now a piece of cake, it starts on either cylinder, although I do like to try and find the rear cylinder just for practice. The machine ticks over very nicely with some stock 289 carbs. My only complaint, and it is most likely not the mag's fault, is that my mag cowl may very well be "rich" in casting and although I have removed lots of material in anger, I still cannot get the cowl to sit as flat as it did with the stock unit as it fouls the coils. ............

Best,
Carl Hungness

You may find that altering the stainless steel flat strip coil bracket you can get a better fit. I made up my own bracket but by twisting, shortening or making a longer bracket you can get the result you want.

 

[vibrac]

On the Egli racer we fited the BTH coils (4 of them for twin plugs) up under the tank so distance from the unit is no problem there is no real need to stick em under the cowl (hells teeth you would be hard pressed to find a more exposed coil than a naked 'D' :-0) Yes it would seem that the coils are the problem part of the BTH setup I wonder how matched they are to the electronic gubbins?

 

[CarlHungness]

Hi:
Can you tell me how to include photos with my post? I posted a reply about the kickstart cover and a mod I made to eliminate the stock G97 & G98 but don't know how to post a photo of my mod. Thanks, Carl Hungness

 

[bmetcalf]

I the row of icons above where you type your message, click on the square with a tree in the middle.

 

[davidd]

I have to agree with Tim and Carl. I have had the BT-H on the racer since 2008 and I have never done a thing to it. You can not do this with a stock mag. I do understand that this is also the bad part, namely, if something is going wrong there is nothing that you can do but send it back for repair. This is a larger hurdle for someone who wants to control everything, which most of us do. However, if you are racing you are almost required to carry as spare. At Bonneville when Kurt Carlson's mag failed it was taken apart and made to run, but it would not work as well as necessary for racing purposes. In effect, the only solution that could have helped would have been to put on a spare that was up to snuff. If you are riding on the street there is a big advantage to being able to limp home.

I think the BT-H is a big improvement. I also recognize that there have been some unhappy customers. I have to say that I suspect the failure rate is lower than stock systems. Having said this, I am a big fan of the "D" ignition on a street bike even though I have developed a good deal of confidence in the BT-H.

In terms of problems with the BT-H, I have had two: lack of a good ground on initial installation and one coil may have gone bad. I had a spare and swapped it out without testing it.

David

 

[CarlHungness]

Hi:
I am on the Quick Reply section right now...and I don't see NO tree Bruce.But I did click on some squarish thing and think I got it...My latest sculpture of the SUMAR Indy 500 car, 44" long. I am clicking on all the icons and I don't think I have the IQ to sort them all out, or the interest. Thanks, Carl H