Heymow - Lawnmower Racing Forum

Engine Help => Kohler Engines => Topic started by: Tom Cole on November 22, 2012, 07:08:00 am

Title: Coming soon from ARC...
Post by: Tom Cole on November 22, 2012, 07:08:00 am
We are almost finished with a flywheel for the v-twin and have started on connecting rods.
Title: Re: Coming soon from ARC...
Post by: FlatheadPuller on November 22, 2012, 07:07:17 pm
What piston are the vtwin rods going to be used with. The stock pistons are junk. Kerber and super cub already have rods made for pistons they use. Both being JE. Lakota uses JE pistons as well.
I ask because Blossom racing has pistons that will fit that are ultra light and use the .490 wristpin. Not sure what bore sizes are availible but the pistons blossom sells are JE and Wiseco and are a nice option if ARC considers it. Bore sizes from 3.032 to 3.327 will cover most everything.
Title: Re: Coming soon from ARC...
Post by: Burton for Certain on November 22, 2012, 07:29:20 pm
Yup. Super Cub, Lakota, AND Kerber already make all the parts for these engines.
Title: Re: Coming soon from ARC...
Post by: Tom Cole on November 25, 2012, 08:17:53 am
Rumor has it that JE is getting out of the Jr dragster piston business, so Blossom called us and asked us to get behind an effort to supply and stock wiseco alternatives.  It requires a big investment because wiseco wont stock them.  That is all beginning to come together now.
We will likely make rods for the stock pistons and the wisecos.

Title: Re: Coming soon from ARC...
Post by: FlatheadPuller on November 25, 2012, 04:49:08 pm
I would not waste time and tooling expense for making rods for stock pistons in a command twin. They are junk. Wiseco yes. more so if your using the .490 wrist pin piston. The stock pistons in an open rpm motor are just lit fuses waiting to let go.
Title: Re: Coming soon from ARC...
Post by: GRUBDIGGER on November 25, 2012, 05:55:21 pm
ANYTHING IN THE WORKS FOR A KAWASAKI V TWIN? FLYWHEEL? ECT.
Title: Re: Coming soon from ARC...
Post by: Cromwell C4 on November 25, 2012, 06:09:25 pm
I would not waste time and tooling expense for making rods for stock pistons in a command twin. They are junk

I second that. I wouldn't mess with making anything for the stock pistons. You would only sell a hand full at most.
Title: Re: Coming soon from ARC...
Post by: FlatheadPuller on November 25, 2012, 07:49:29 pm
I can tell you a good idea racers will like is having a magnet in the flywheel so you can run stock coils. It will lower the cost of the wheel I believe. Other wise you have to run dual 12volt coils that arent stock appearing for some classes.
ANYTHING IN THE WORKS FOR A KAWASAKI V TWIN? FLYWHEEL? ECT.

I would make parts for these engines before the commands unless the prices are going to be far less then the puller guys that already make the command parts.
Title: Re: Coming soon from ARC...
Post by: Burton for Certain on November 25, 2012, 09:14:56 pm
There are stock replacement flywheels that use the stock coils or you can use the Briggs coils.
Title: Re: Coming soon from ARC...
Post by: FlatheadPuller on November 25, 2012, 09:21:22 pm
Midwest make those Drew? I havent seen them I guess. All I have seen is the aluminum wheels that have to use the crank trigger parts.
Title: Re: Coming soon from ARC...
Post by: Burton for Certain on November 25, 2012, 09:53:32 pm
Yup. They made them 3 years ago and still make them. Adjustable timing. Can use Briggs coils with a shim.
Title: Re: Coming soon from ARC...
Post by: Cromwell C4 on November 26, 2012, 01:50:21 am
Yup. They made them 3 years ago and still make them. Adjustable timing. Can use Briggs coils with a shim.

Midwest makes an aluminum flywheel that uses the stock Kohler coils only, and the stock Kohler coils aren't too great. The Briggs coils aren't even close to working with it. The Briggs coils are bigger, will hit the intake if you put them in the stock location, and are a different bolt pattern. You would have to make the flywheel diameter smaller and use coil brackets, as well as use a different magnet, which is what ARC is doing. It will be a great option to guys that don't want to run electronic ignition, but want a hotter than stock ignition.
Title: Re: Coming soon from ARC...
Post by: tractorracer12 on November 26, 2012, 05:53:27 pm
The midwest flywheel with the stock magnet will only work with kohler coils.The polarity in the magnets are different than the briggs flywheels. Yes you can get a briggs coil to fit the kohler. But the kohler magnets pull push pull with the polaritys, as where the briggs coils push pull push. confused?? i used a magnet to try one from the other. i had a set of briggs coils mounted on my vtwin, but didn't have any spark because the polaritys was different. all i know is it didn't work lol.   with a little coil bracket and a set of briggs type magnets with briggs coils you would have a good setup. just a thought but that would be the setup i would mass prodouce if i would sell them.
Title: Re: Coming soon from ARC...
Post by: big jerm on November 26, 2012, 06:59:20 pm
What will be sweet will be use the same outer flywheel as the intek so all I have to do is buy a new hub if I ever decide to switch over
Title: Re: Coming soon from ARC...
Post by: Tom Cole on December 11, 2012, 08:36:40 am
The flywheel is going into final testing mode tomorrow.  It is made with a 6611 flywheel body, so if you already have a 6611 type flywheel, you will be able to convert that flywheel by purchasing the correct hub, coil brackets, and ring gear/standoffs.

This flywheel is designed to use the Briggs Vanguard/Model 28 coil.

All I know about the engine it is designed for is that everyone calls it a Kohler V-twin or Command V-twin.  Is there a more specific name?  Also, is there a family or range of HP/cc ratings that can all use this flywheel?
Title: Re: Coming soon from ARC...
Post by: stahlwerks on December 11, 2012, 11:31:04 am
For gas powered engines we've run the stock Kohler coils and made power up to 10,000 rpm so I don't know whats up.  I think its probably because your running the wrong type of coils, you need to use the coils off of the 18hp Kohler Commnad, the ones with the rectangular side legs, not the ones with a cut out on them.  We build our $2000 engine special for lawn mower racers and pullers all the time and use those coils with no problems at all, so as far as the Kohler coils don't work your all wet, but some types don't.  I wouldn't condemn a product that works if you don't know all the facts about the various types under that name.

JE may stop making JR drag racing pistons that strange, but what in the world does that have to do with us.  All of our pistons are custom made either from JE or Diamond for our application, we don't try to shoehorn in junk that it isn't made for it because we have it setting on the shelf.
Title: Re: Coming soon from ARC...
Post by: rceagle1a on December 11, 2012, 01:24:25 pm
Tom, Since the wheel I have on my Intek twin will work on a kohler twin with an update, What is the chance that the 28/31 briggs single wheels will be the same on a Kohler Single?
Title: Re: Coming soon from ARC...
Post by: Tom Cole on December 11, 2012, 01:49:17 pm
stahlwerks: the coil change has to do with two things.  1. It is what we were told was desired, and 2. we wanted to use what we already knew would work with our existing magnet configuration.  As a side note, the ability to utilize the 6611 body as a base means we don't have to create a "special" part for specific engine that may not represent a very large market.  This makes the part less expensive.

If you have to change the coils from what comes stock anyway, why does it matter which coil is chosen?  The Vanguard coils are inexpensive and proven with our flywheels.

As far a shoe-horning junk sitting on our shelves...we are designing the rod and likely making the bearing as well, so we can make it to whatever specs we want.  Wiseco stocks a great deal of larger pistons for motorcycles and such and these pistons are less expensive than custom stuff.  The pistons are the same as what you would get if you had custom wrist-pin holes and such, so we aren't shoe-horning junk, but rather we are adapting an existing proven setup with a product where we can choose the configuration.

rceagle1a: I've never seen a Kohler single...so I can't answer your question. sorry.
Title: Re: Coming soon from ARC...
Post by: FlatheadPuller on December 11, 2012, 03:39:35 pm
Command vtwin. 18-30hp all the same flywheel. And most all the other parts except a 30 has a little bit more stroke then the rest of them.
Title: Re: Coming soon from ARC...
Post by: Tom Cole on December 11, 2012, 03:41:43 pm
Thank you
Title: Re: Coming soon from ARC...
Post by: Tom Cole on January 02, 2013, 07:39:53 am
Command vtwin. 18-30hp all the same flywheel. And most all the other parts except a 30 has a little bit more stroke then the rest of them.
Are the rods the same in the 18-27HP?  There is an offset built into the rod at the main journal end on the 18 and we figured that offset changed as the bore size went up.
Title: Re: Coming soon from ARC...
Post by: FlatheadPuller on January 02, 2013, 01:19:56 pm
rods are the same.