Webber 750 engine

You will have some Weber fans back here in the USA pulling for you to win . I really can appreciate how you are experimenting. I don't know if one O2 sensor is better than another, however, Bosch claims that a new o2 sensor can improve the performance over a well used sensor.
http://www.boschoxygensensors.com/
 
HI Mark

In your post #1211, you mention a counter balance instead of a flywheel, and a recess machined in the "new" plate?? What thickness of plate are you going to use and how thick is the counter balance going to be, will you still be trying the Rotax box??

Tony

Tony,
This is the ruffout of the new bellhousing.
1 you can see the scribed lines for the flywheel cover and the motor support feet.

2 will show you what I have for the flywheel to recess into. Its about 24 lbs right now but there is lots and lots of alum to remove.
 

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There's gonna be a might big pile of shavings there !!! Will be intersesting to see what it weighs when you are finished. How will you find your centers for the dowel collars on the 3 bolt holes in block and then reference the crank center, DRO??

Tony
 
There's gonna be a might big pile of shavings there !!! Will be intersesting to see what it weighs when you are finished. How will you find your centers for the dowel collars on the 3 bolt holes in block and then reference the crank center, DRO??

Tony

Yes , lots of shavings. I added DRO to this little mill and it is helpful, but for this piece it was faster to just use the old faceplate as a template. I started with the center for the crank and worked outward from there.

I weighed what I have cut out so far and it is 19 lbs on a bath scale. I see another 5 lbs of material to be removed from the side profile. Then I will start cutting in the recess for the flywheel and determine what I need for the C box.
 

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mounting a "C" box

mounting a "C" box

Hello,

The "C" box is meant to be mounted on a round "feature" to keep it centered. When you are machining that feature, make sure it is dead center on the crank and you will save youself alot of wear an tear on the coupling between the crank and the gearbox.

Jason


Yes , lots of shavings. I added DRO to this little mill and it is helpful, but for this piece it was faster to just use the old faceplate as a template. I started with the center for the crank and worked outward from there.

I weighed what I have cut out so far and it is 19 lbs on a bath scale. I see another 5 lbs of material to be removed from the side profile. Then I will start cutting in the recess for the flywheel and determine what I need for the C box.
 
Thanks Jason,
On post 789, I have a centering Ring to line up the Cbox, on this new adapter it will be machined into the face, rather than an extra component.
 
Mark, I'm getting lazy, do you know which cylinder is designated as # 1 (without me going all thru the manual. Am wiring the coils and injectors and would like to get the wiring moulded in the right direction the first time, so far no more wiring screw ups (I think).

Got the pump and instructions ready to ship, but am looking high and low for the mounting kit.

Tony
 
Tony,
The cylinder on the Mag end or Alt. end. It has the cam sync. I don't remember if you have the reversed head or not. If so look for the Hall sensor on the valve cover and that will be number one

Just when you get the pump together send me a PM and I will give the address and tell me how to pay you. I already have a pump so its no hurry. I took a few pictures of the VR wheel when I took the cover off, if you need it for anything. I bet you are really getting excited to have your ECU wired up.

I looked on the Microsquirt forum tonight, I did not see much of anything on the Weber or Polaris. Maybe I was looking in the wrong place.

I finished cutting the profile out for the bellhousing and weight it at 14 lbs. I hope to bring the weight to 4 to 7 lbs when finished
 
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Thanks for that info Mark, yup I have the reverse head, so the cylinder on the PTO end will be # 1. Glad to see a little progress on the wiring for sure, but last time I was excited was when I thought I had screwed up on the fuel pump wiring :) I'm getting to old to get to excited to often, it takes to much energy :)

Tony
 
Anybody know what a Weber snowmobile crankshaft weights?

Also, I ran across another brand of ECU that is ideally suited for the Weber. It is made by Electromotive ECU. It will be the "TECs" model. It is already setup for the 60/2 trigger wheel and Cam Sync. ,
It has sequential injection and Coil on plugs. I spoke with the factor rep today. It sell for about $1240 and you can down load their tuning software for free if you want to play with the program. There are manual's on the support page that can be downloaded as well.

The only drawback I see to this ECU at this time is the circuit to the coil may be too much for the Bosch coils. This company is known for its hot spark ignitions. They will test your coils if you send them to the company and let you know.

They also make a unit that will handle a 3cyl. I forgot who made the comment about wanting to try something with the Yamaha. 3 Cly. Was it Hobby Cad?

http://www.distributorless.com/ I added link to Weber link thread
 
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Any word on how Neil is doing with his redrive, I realize he just kind of comes and goes on here, but I think I would rather have his 3 gear than to build my own tractor belt drive, I have access to a wrecked low mileage sled but I need to make certain that a redrive is available. I guess having him go slow and making no promises is better than some in the industry making promises and not delivering after taking your deposit. off topic but has anyone heard anyfirst hand news about the thunderaviation motor?
 
I have not hear anything since Neal posted his 3 gear drive. He will probably post something amazing pretty soon. \

Tony,
I have cut out the basic shape and the majority of the flywheel pocket. Its down quite bit on weight. I did not weigh it at this point. There is still a lot of cutting to do on the face, a small amount on the profile.

I test fitted it to the Weber today. I can work on the motor support still, but the rest is waiting to see what the damper will look like.

Heres two shots to give you an ideal
 

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Hey Mark

that is looking really great, that housing would work on any of the boxes like Hirth or Rotax or Simonini. All that would have to be alltered would be the "exact" diameter of the "centering" hole for the box and the bolx mount holes. To bad that was not done on and CNC, you probably could get a lot of interest on repeats.

Tony
 
Mark

A thought just occured to me (that twice this year) . If your mount/adapter works out well and you become one of the most popular guys on the forum, could that mount be translated into a CNC program for rapid production ???? It would be very expensive but some may want it, I think the aluminum alone would be about 4 to 5 hundered bucks ??

Tony
 
That is looking good, I wish I had thew equipment to do that type of work, but I haven't had the chance to do any machining since I was in college, If you were able to do it by cnc I have to agree that it would be a great way for people to start using the weber, I personally want to see the bugs worked out as it seems some people are to fasst to rush their project to market and then business goes downhill as they find the problems after they sell them. Good luck and I hope yours works out for you, keep up with the pictures and reports.
 
Hey Mark

After doing the ground strap mods to the ignition coils on the Weber it is very clear the designer of the coil "intended " for the coil body to be grounded to either the valve cover or to the engine some way, because when you take a close look at the coil, "one" of the mounting bolt holes has a "exposed" metal strap moulded into the bolt hole. The modification states to place a "serrated" (star washer) under the strap and between the strap and the coil. Takes about 5 minutes to install both. I made mine out of some of the 3/8 flat shielding braid that I used on the wiring, just crimped and soldered ring terminals on the ends and covered with some heat shrink. The commercial ones look to be from about 10 guage stranded wire, don't know why such heavy wire, no great amount of current involved. The other end of course goes to a valve cover bolt near by. Strongly recommend this mod.

Tony
 
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Tony,
If the bell housing works out well, It can be reproduced for about 400 dollars totally. Thats machining and Alum. You would still have to supply the gear box of your choice and a suitable flywheel. It might be easier to make a cast from this one when it is finished. I am still learning the CAD so I will have a file for CNC.

I know the bell housing looks mighty ruff right now, but it will clean up to a nice piece.
 
Setup CD II

Setup CD II

Update on the Setup in the CD II with 2-Stage Belt Drive and Flywheel

John
 

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Mark,

I sure hope you did not over machine your housing. Did you consider leaving in a machined gusset due to the length of the mount tabs? I looks like it will turn out really nice once you clean it up, but just a thought to consider.
 
Update on the Setup in the CD II with 2-Stage Belt Drive and Flywheel

John

We have missed your post John,
I can't say much about your belt drive, except what is showing is really beautiful machine work. The body work around it is so first class:first:

I hope it is a big hit in sales!
 
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