Cam Chain - Check if TDC is Correctly Set

[peanut]

well that seems conclusive enough paul great post. I have to say that a picture speaks a thousand words and saves viewers speculating .

I must admit I am finding this issue a real struggle to follow at the moment as I am suffering with Vertigo . I read and reread Grizld1's post last night and still couldn't follow it . its a complicated association to keep in correct relationship in your mind when you can't see straight or concentrate properly.

If the crank and cam indexing is correct then the only other potential issues must be the Fully advanced mark or the Boyer module is faulty.

Once the Boyer pcb is clamped in place there is very little retard/ advance adjustment allowed as the slots are short.

If the crank is set at the fully advanced position and the camshaft index mark is vertical.... then clamping the Boyer magnetic rotor to the camshaft with the white dot visible in the pcb hole should theoretically get the timing very close to being spot on.

The pre-programmed Boyer chip adjusts the advance and retard according to the rpm of the camshaft and produces a spark at the correct time by its register of the relative positions of the rotor magnets and pcb coils in relation to the cam and crankshafts fully advanced position
It should only require a very small adjustment of the pcb plate to tweak the timing with a strobe.

The position of the camshaft relative to the fully advanced position is sensed by the position of the pcb coils in relation to the rotor magnets and that data is transmitted to the Boyer module. So if the fully advanced timing mark is correctly marked ,it does suggest that there is something wrong with the Boyer module or the processor rather than anything to do with the magnetic rotor, pcb board coils or the position of white dots

 

[grizld1]

There can't be a timing mark issue using the drain slot for an advance timing mark unless the left engine cover is faulty; only the plate with retard/TDC marks is movable and subject to error. I've found the spot out of sight when a BB ignition was set to full advance more than once, and the motor ran flawlessly. But there's one possibility for error here. Paul, if you didn't wind the motor up until the rotor mark stopped moving left--that is, until full advance was reached--the outcome would be the alignment of hole and magnet that you describe, and you'd wind up with timing set too far advanced. Now don't panic or fret! On my own machines I've seen alignments of hole and trigger farther out than yours with no flaw in operation from idle to 8K rpm (and yes, the motor is built to take that)--I'm talking about how things are, not how they should be. Peanut isn't going to like this opinion, but as we discussed earlier by PM, the BB setup for the XS650 is a crude beast at best. (When that Gill coil goes south on you, don't waste money on another like it; use a 0.6 ohm coil from another maker--any other maker.)

I don't know why trigger and pickup alignment can vary at the point where the spark flies with the BB, but one feeble guess would be that magnet strength may vary a bit from unit to unit. If you have good starting and strong spark and the strobe shows full advance, the control box is doing its job. Anyway, recheck with your strobe to be sure you're reading the marks at full advance, then be happy--that paint spot doesn't matter!

 

[Paul Sutton]

I put everything back together again and rechecked the timing. The bike is idling nicely so took it for a 15 minutes spin. It certainly feels much smoother than with the old stock ignition. The old vibrations seem to be smoothed off.

Thank you for all your time and thought in helping me come to a conclusion. I will add some more photos later in the week to show where I installed the BB box and ignition coil, or do you think I should copy everything over into a new thread call "Boyer Bransden Ignition - XS650 SH".

Thank you.

 

[5twins]

That might be a good idea. There isn't much posted about the Boyers. That would make the info easy to find in a search.

 

[grizld1]

One thing to watch for, Paul: I struggled for weeks one time trying to figure out why I was getting a vicious misfire and wonky reading from the electronic tach every time the revs hit 6K rpm. I finally pulled off the Boyer timing plate: the wretched thing had warped, and the rotor had left marks on the solder pads on the back. I cut the pickup coils off the old plate, flattened it, slathered it with epoxy, and slipped it over the coils of a new plate for reinforcement. That ended the grief, and I used that setup until I decided to try a Probe ignition, after which I never looked back. Sadly, few folks wanted to pay a few dollars more for a lot more quality, and Mark Whitebook had to drop the ignition systems from Probe Engineering's offerings because they were costing him money rather than otherwise.

Anyway, your thread will be a great help to others. You're doing things the right way, with attention to detail and voicing intelligent concerns. Enjoy the ride!

 

[peanut]

There can't be a timing mark issue using the drain slot for an advance timing mark unless the left engine cover is faulty; only the retard mark is movable and subject to error.

I don't know why trigger and pickup alignment can vary at the point where the spark flies with the BB, but one feeble guess would be that magnet strength may vary a bit from unit to unit.
Anyway, recheck with your strobe to be sure you're reading the marks at full advance, then be happy--that paint spot doesn't matter!

I've read about the drain slot roughly aligning with the Full Advance but have no experience checking it or working with it so I always check all timing marks from scratch with a degree wheel or protractor to be certain in my mind and I can then eliminate it from the equation.
It occured to me that as many of the BB modules are placed in identical plastic boxes it must be possible for BB to put the wrong label on a box or shove the wrong module in a box or use the wrong program/chip
but as you say once the crank and cam are indexed a strobe will get you where you need to be regardless where the magnets and coils end up.

You seem to be unlucky with the BB units . I've never read of one not working or being faulty .
If you do a google search for faulty or not working boyer bransden you'll not find many results if any and they have been producing them since the 60s.

 

[grizld1]

Well, Peanut, you've read about one now; of course the plate didn't warp for a few thousand miles, and I'd used another unit that got mangled in a crash (don't ask!) for many thousands of miles without warping, so I'd chalk it up to a vulnerability, not a common problem.

There was a first-rate article on BB installation posted on the old 650 Rider site by a member from one of the Scandinavian countries years ago; can't recall his handle, though I should. If there's an archive and anyone knows how to access it, it could be very useful. He did quite a few interesting things; machined his own PCB spacers with an extension on the outside edge that reached all the way to the floor of the ignition housing, for example, so that the spacers had support all the way around instead of hanging off the edge of the boss.

Edit: That thread was by Goran Persson, from New Zealand--I even got the hemisphere wrong, and on two axes to boot! I'm digging through old threads at XS650 Garage, he may have posted his article there. I'll post a link if I can find the thread--it was beautiful work.

 

[peanut]

I've only fitted the one to my existing bike and it worked first time with no adjustment and I am more than pleased with its performance. Their installation guide and marketing literature is appallingly naff and probably hasn't been upgraded in 30 years.

I guess the considerable heat and hot running engines in various parts of the World could cause problems with the electronics ....its not a problem we are ever likely to suffer with in the UK

Thanks for the link I'll check it out

 

[grizld1]

Found Goran's thread; it was at XSs650 Garage. There wasn't much detail, just a link to photos and a few notes at www.photobucket.com/albums/v463/GoranXS650. It's still up and well worth a look. Goran did a writeup with step-by-step detail somewhere, but I can't find it; Bertaut's site, maybe? Anyway, the man does some of the cleanest thinking and cleanest execution that I've seen.

 

[peanut]

Found Goran's thread; it was at XSs650 Garage. There wasn't much detail, just a link to photos and a few notes at www.photobucket.com/albums/v463/GoranXS650. It's still up and well worth a look. Goran did a writeup with step-by-step detail somewhere, but I can't find it; Bertaut's site, maybe? Anyway, the man does some of the cleanest thinking and cleanest execution that I've seen.

excellent........... thanks for the link I'll get a coffee and some cake and sit down and enjoy it
.so much to read so little time

 

[650Skull]

This album has a bit of a write up in each pic for the BB. Save a long search
http://smg.photobucket.com/user/Gor...Project/Boyer Bransden Ignition?sort=4&page=1
His site is well worth a bookmark

 

[650Skull]

From Goran Pearsons Album
http://smg.photobucket.com/user/Gor...Project/Boyer Bransden Ignition?sort=4&page=1

Supplied Aluminum Spacers tend to Tilt when the screw is tighten. This can cause the Pick-Up Circuit Board to Deform.

Supplied Aluminum Spacers Replaced with New Made Stepped Aluminum Spacers. Machined by John Saywell - Keppel Engineering.

 

[peanut]

This album has a bit of a write up in each pic for the BB. Save a long search
http://smg.photobucket.com/user/GoranXS650/library/XS650 Tinnis Project/Boyer Bransden Ignition?sort=4&page=1
His site is well worth a bookmark

bookmarked ! cheers ....well found

 

[650Skull]

Been using his site for years. Posted many links in threads for reference.