heymow.com - Lawn Mower Racing Forum
July 31, 2014, 12:33:32 PM *
Welcome, Guest. Please login or register.

Login with username, password and session length
News:
Want to Join our site? CLICK HERE
 
  Home Help Search Calendar Staff List Links Login Register  
  Show Posts
Pages: [1] 2 3 ... 75
1  General / Coffee Shop / Re: Tillotson HR Questions on: July 29, 2014, 12:38:12 PM
I agree with the under load tuning. I remember it was the only way to adjust them on a snowmobile was to ride them down a good straight away and tune to the highest rpm then 1/8 turn rich to keep from burning the piston. Now on the question of a remote fuel pump, should I use one and what modifications would I do to the carb? Do I unhook the pulse from the carb to use on the remote pump or do I run both pumps?

Lester
2  General / Coffee Shop / Re: thumb throttle on: July 29, 2014, 08:56:01 AM
Just give him a centrifugal clutch. If anyone has a problem with that they are heartless and don't belong in mower racing.
Just my opinion Wink

We would allow the same in our club (I'm assuming  Wink ) but use as low  of a engagement as possible. It's one thing to allow something that is otherwise not allowed for this reason but to use the allowance for a performance gain would not garner much support.

Lester
3  General / Coffee Shop / Tillotson HR Questions on: July 29, 2014, 08:15:02 AM
Well I remember from my youth having snowmobiles with these carbs on them. Not the best carb but easy to tune and repair. I'm running one now on my OHV single and I have a few questions. 1. Why are all the carbs I see used on mowers mounted upside down compared to snowmobiles? 2. The carb I have has an external pulse (3 plate). I've been told to lose the pump and feed it with an external pulse pump. any truth? (using intake pulse - know how to do that correctly) 3. I have rebuilt the carb and it seems to work ok usually. It doesn't tune like it did when we would tune 2 strokes with them. I guess I need a lesson on tuning these things. I'll take all the help I can get.

Lester
4  Engine Help / Briggs OHV & Vanguard / Re: nikki two barrel carb problems on: July 24, 2014, 08:43:20 AM
Fuel is naturally pulled to the bottom cylinder by gravity so it will run richer than the top. So they use a smaller jet to the bottom cylinder. At higher rpm it is less prevalent so equal jetting works as well. There are other things that can be done to take advantage of this extra fuel....

Lester 
5  Engine Help / Briggs Flathead / Re: 18HP Opposed Twin Performance Upgrade Path on: July 14, 2014, 06:09:20 PM
I also have a bent Geinger I'd let go of CHEAP!!! lol

Best thing to do is to copy the pressure lube block. I had a block that was fully ported and clearanced for the 46 crank and I used a 40 base for my pressure lube sump. I just looked at where the oil passage was and tried my best to copy it.

Lester
6  Engine Help / Briggs Flathead / Re: 18HP Opposed Twin Performance Upgrade Path on: July 10, 2014, 08:54:17 PM
Or center drill your splash lube cam and machine the pump drive.

Lester
7  Engine Help / Briggs Flathead / Re: 18HP Opposed Twin Performance Upgrade Path on: July 09, 2014, 09:25:51 PM
It can be done. But if you want serious power out of an opposed the real ticket is to purchase a new block from Briggs. You can still get a special 46 cube block that was built with 31 cube pistons and a 42 cube crank. It never came as a pressure lube so the oil passages must be drilled. Then add a pressure lube 46 cube long stroke crank. Now you have some serious cubic inches to play with. I personally never built this engine but did assist a fellow racer in doing one. I also showed him how to drill the oil passages. It is actually only one long passage that hits the top of the cam and exits into the top journal Iit will exit above the journal and just under the top seal). Then a short one to connect to the top journal. This oil passage feeds the top rod and top crank journal.

Lester
8  Engine Help / Briggs Flathead / Re: ISKY CAM OPPOSED TWIN on: July 08, 2014, 12:20:38 AM
Pressure Lube Cam?

Lester
9  Mower Building / Setup Help / Driveline / Re: need help with 700 tranny on: July 07, 2014, 10:43:07 AM
we run a bit higher (numerically lower) ratio on our Mod-XR. We are in the 4.50 range and at our last race was at 4.22. We do however run a Kawasaki 540 and keep it governed at closer to 3560. It makes more power there than if we push it up to 3650. Plus we never need to worry about failing post race tach check.

Lester
10  Engine Help / Briggs OHV & Vanguard / Re: Intek Ignition Diode on: July 04, 2014, 01:10:59 PM
thanks Jim.

Lester
11  Engine Help / Briggs OHV & Vanguard / Intek Ignition Diode on: July 03, 2014, 12:11:21 PM
I have an Intek that we have lost the original coil kill wire for. I'm going to run down to Radio Shack and grab some but I don't know exactly what I'm looking for. Some one know what I need?

Lester
12  Mower Building / Setup Help / Driveline / Re: need help with 700 tranny on: June 30, 2014, 09:05:10 AM
Bigger front sprocket or smaller rear. It's about gear ratio. Understanding them is going to be your best friend.

Lester
13  Engine Help / Briggs Flathead / Re: Oppy Carb Issue on: June 29, 2014, 12:53:49 PM
Turn the carb around with the pump facing the shroud.

Lester
14  For Sale / Trannys / Axles / Wheels / Re: 820 TRANSAXLE AND 739 TRANNY on: June 19, 2014, 10:43:02 PM
Thanks Ed.  bash LOL

Lester
15  For Sale / Trannys / Axles / Wheels / Re: 820 TRANSAXLE AND 739 TRANNY on: June 19, 2014, 10:42:44 AM
No response?

Lester
Pages: [1] 2 3 ... 75
Powered by MySQL Powered by PHP Powered by SMF 1.1.18 | SMF © 2013, Simple Machines Valid XHTML 1.0! Valid CSS!


Google visited last this page July 25, 2014, 08:49:55 AM