GS1000G mods- big bore and fuel injection

[coombehouse]

Ref the problem with the 36-1 trigger, if you look at the picture I posted you may be able to see how I did it. Its easiest to make a whole new mount with a cutout at the rear to locate on the dowel in the crank & a flange on the top to bolt the wheel to. You will also need a new baseplate as the pickup needs to be moved outboard as the new trigger is a larger diameter. It all work & it was easy for me to make as I have the equipment at home. As I am in England getting the wheel was easy too for a change. If you want more pictures let me know & I will take it apart tomorrow & post some. Nick

[GS1000G Shopper]

I have a program called E Machine Shop. It's a lot of fun, I designed some pistons (OEM had been discontinued) for some ST1100 brake calipers. I used it to design a 36-1 wheel that is 2.5" in diameter and would bolt on in place of the advance unit. I sized the notch, but it would need proper alignment. Also, the distance between the pickups is only 1.2", so the wheel would likely need to be much smaller. The case cover for this part of the engine is 4.9" in diameter. I'm going to experiment with making a smaller diameter wheel, with fewer teeth.

Here are some pics of what I ended up with. The cost would be prohibitive for just one.

[GS1000G Shopper]

One other alternative would be to machine a spacer with a notch in it and a center hole, and then bolt a small trigger wheel to it. There is not much room to work with things here, the diameter of the end with the notch is .95", so really small screws would be needed to bolt a 1.2" diameter wheel into place, and then it would need to be perfectly centered. I think a one piece as I've laid out would be better.

Here is a pic with the wheel scaled to 1.20" diameter:

[coombehouse]

Nice looking models. I would suggest making it in 2 parts. Make the centre boss with a shoulder & the hole in the trigger sized for an interference fit. Align it fairly closely, heat & freeze & press together. It won't move. Any adjustment can be made via the slotted holes in the baseplate & the offset in tuner studio. The teeth on most triggers are more of a squared off shape rather than like gear teeth. Would be easy to make with a dividing head & mill with a slitting saw or a small diameter cutter. Or laser cut if you know someone.
You would need to make the pickup slightly adjustable too as the gap between the tooth & the sensor was critical on my bike. Bit of trial & error & logging fixed it.
Nick

[GS1000G Shopper]

It's a challenge to design. I have to start with a gear in E Machine shop, or use a dxf file I found for a 36-1 trigger that is huge. I may be able to have more luck with fewer teeth on the wheel. I found a low cost pickup that could be installed in a bolt and filled with epoxy. The cost estimate I got for 1 trigger wheel was around $165. I know there is no market for these, so I will stick with my welded unit for now.

[GS1000G Shopper]

I'm wondering what would happen if I just used the 1-4 pickup with the VR1 input? My spark outputs are tied together in Tuner Studio no matter what input setting I use. I have to wonder how would the MS know when to fire 2-3? A 36-1 wheel only senses the engine at one location, as the single tooth OEM pickup does.

This part is far more complicated than I ever thought it would be.

[coombehouse]

I'm wondering what would happen if I just used the 1-4 pickup with the VR1 input? My spark outputs are tied together in Tuner Studio no matter what input setting I use. I have to wonder how would the MS know when to fire 2-3? A 36-1 wheel only senses the engine at one location, as the single tooth OEM pickup does.

This part is far more complicated than I ever thought it would be.

That is what I use with the 36-1 trigger. You programme the ms so that it counts the teeth from the gap. It therefore knows how many degrees away from that position the firing point is for 1 & 4 so it then fires 2 & 3 180 degrees later. This all well documented in the manuals for ms & ms extra. I believe that the greater the number of teeth the better the timing accuracy as when accelerating the time between pulses will vary so the teeth allow more accurate prediction. That is my understanding. Does this make any sense. I think by using the OE dual trigger setup with only 1 tooth there will be very imprecise prediction for advance.

[GS1000G Shopper]

I'm not even getting any backfiring now, so it's getting worse not better. I have not tried the single pickup. What I'll likely do is just unbolt the 2-3 pickup and try to start it w/o the side cover on.

EDIT
Looking at the stock pickup/advance unit, the slot in the part that fits on the crank is 90 degrees opposed to the tooth. The GS uses a 17 degree BTDC setting at idle (< 1500 RPM), so I think I can make heads & tails of this.

I'm about ready to ditch the B&G 3.78, the Microsquirt forum is a ghost town. I had one reply to several posts, and it chastised me for pointing out a link did not work on a thread I "resurrected" (it was a pinned/sticky post, so I figured it was one meant to be used for reference). Apparently I'm not the only one that has had this experience:

http://xjbikes.com/Forums/viewtopic/p=370987.html

I need some help with my setup and the microsquirt forums suck!! No participation on there.

[coombehouse]

I'm not even getting any backfiring now, so it's getting worse not better. I have not tried the single pickup. What I'll likely do is just unbolt the 2-3 pickup and try to start it w/o the side cover on.

EDIT
Looking at the stock pickup/advance unit, the slot in the part that fits on the crank is 90 degrees opposed to the tooth. The GS uses a 17 degree BTDC setting at idle (< 1500 RPM), so I think I can make heads & tails of this.

I'm about ready to ditch the B&G 3.78, the Microsquirt forum is a ghost town. I had one reply to several posts, and it chastised me for pointing out a link did not work on a thread I "resurrected" (it was a pinned/sticky post, so I figured it was one meant to be used for reference). Apparently I'm not the only one that has had this experience:
http://xjbikes.com/Forums/viewtopic/p=370987.html

I expect I have all these problems to come. As yet I have not completed the mechanical side of the injection parts. I concentrated on getting the ignition side of things to work before I removed the carbs just to be able to isolate any future problems I may have. I guess its too late for you to try this now.

[ArttuH]

Some food for thought for trigger wheel implementation.

Here is the setup that I have been using by this far.


It uses two hall sensors, the trigger wheel is made of aluminum and there are magnets mounted in the wheel to trigger the sensors.



The wheel is mounted on the crank with a short intermediate shaft. The mounting bolt clamps the wheel on the shaft and original 19 mm hexagon "nut" is also included to provide a way to rotate the crank with a wrench.

Recently I switched to MS3 ECU and to sequential injection / ignition with camshaft sensor. It seems this setup would benefit from better crank trigger resolution so now I'm making a new trigger arrangement.



The sensor is some generic VR pick-up and the wheel is laser cut from 5 mm thick mild steel. Mounting shaft is still under work. The wheel will be welded on the shaft. I hope to get this ready within next few days. Interesting to see if it works like expected.

[GS1000G Shopper]

Thanks. All of my E Machine designs be they 36, 24, or 12 teeth do not pass internal validation, meaning they cannot make the part as designed.

I think I can export the best file and have a 1-piece part made at another machine shop. I have the dimensions needed.

In more bad news, I tried the single pickup and still no start. I detected a small fuel leak under the throttle bodies so I will pull them and see where the fuel is leaking. I can also look at the injectors and make sure they are fueling while I have the TBs off the bike.

[ArttuH]

I have few spare pieces of those 24-2 wheels. I can sell one for quite reasonable money if you like. Or even complete trigger set once I have verified it works

[GS1000G Shopper]

Let me check into a few other options first. Thanks for the offer.

[GS1000G Shopper]

I have made a 2-part trigger wheel setup that shows as being machinable and will bolt on. I looked into the press-fit, but adding to the rear of the wheel makes it difficult if not impossible to machine.

Part 1 is a spacer that takes the place of the advance assembly. It has a notch in the bottom so it fits in to the crank opening. The top has 2x 8-32 holes in it so the wheel can be bolted on.






Part 2 is the 12-1 trigger wheel. I added 4 sets of holes so it can be mounted in various positions. Coupled with an adjustable Hall sensor, this would allow for a great deal of timing variation.

[GS1000G Shopper]

I pulled the throttle bodies today and it looks like the fuel leak was most likely the joint where I had a brass 1/8 pipe fitting in place, but a couple of the small injector o-rings looked bad also. I found some 3/8 aluminum fuel line would fit in where I had threaded for 1/8 pipe, so plan B is to cut a short section, rough up the ends, and use some JB Weld to reassemble it. I can then clamp it in place so it sets straight.

EDIT
The little O-rings are $6.06 each! Time for McMaster.com again. I can likely get 25 Viton O-rings for that price.

UPDATE
I tired several sizes of o-rings that were not a good fit. The size needed based on measuring the OEM ones is a 7.5mm ID x 2.0mm thickness, which yields an 11.5mm OD. McMaster does not sell these, but they do sell a 7.8 x 1.9 that yields an 11.6 OD. A bag of 10 in Viton is about $6.