35HP Vanguard Mods?

[Hollywoodc]

Damn Bro! I have a new found appreciation for these V-twins after watching those clips!

[fmints]

Damn Bro! I have a new found appreciation for these V-twins after watching those clips!

Ohhh Yeah!!!! V-twins are the truth for torque and Hp.

[Hollywoodc]

I tried hooking up the $25 Harbor Frieght Tach the other day and I did get a resposne. I Mickey rigged it just to see if it would work. The instructions say to connect to the distributor, the tach is for a 4,6,8 Cylinder engine.
I kept the switch at 4 cyl., then try wrapping the Distributor wire around the Spark plug wire. I turned the Engine over and got the gauge to climb.
Question:
Being that its made for a 4 cyl. engine, does this mean that it will only be reading half of the actual amount, double, or am I good?

[riotwarrior]

Kinda boring but shows the tach pretty good, same chassis and 23hp engine but different cart. runnin' Team clutches

Golf Cart Racing - YouTube

This is My pulling tractor with a 23hp Vanguard, its runs 8,500 under full load

Creekside Dream 9-13-13 exhibition run 21/23 gear w 20% underdrive - YouTube

sic...absolutly....nuts....I LOVE IT

[Tomo]

hi Hollywoodc ,
Typically on a vanguard u need a programmable tacho
12345678910 cylinder selectable
DIS distributorless ignition system selectable
2-4 stroke selectable
A popular tacho with vanguard engines is the equis brand
If u have fitted another style of tacho it should read around a 1000rpm at idle or u can check engine rpm with an infared noncontact tacho

tomo

[Hollywoodc]

Been awhile since I've posted an update. So I wanted to touch base on whats been going on.
So I got the .060 Shims, installed them and adjusted the valves to .003.

I had a few jets that I tried with the needle clip set in the center groove.
Took it for a few spins to try and read the plugs.
Seemed like it felt best at take off and mid range with a 45 pilot.
But as for the Main jet, The engine kept bogging down before I could get to full throttle, about 3/4.
I started with 180 and the plug looked Rich and still bogged down at WOT.
Worked my way down through the jets I had 170, 165, 160, 155. It all bogged down close to Full throttle but 155 felt like it picked up to the most speed before bogging down.
I don't have any more jets under 155 and when I pulled the plugs, the rear cylinder plug ceramic looked pretty good dark tan but the front Cylinder looked a bit hotter, white Ceramic.

Im starting to get frustrated and confused with the tuning. I don't have the tach yet but I don't think Im getting up to over 4000 RPMS. But the valves are floating rather then the bogging being a jetting problem. I don't really know what valve float should feel like.

Any advice would be greatly appreciated.

Im going to hook up the cheap Harbor freight Tach that I have and see if I can pull some RPM numbers before I go further with changing jets.

[Nubs]

It'll start to miss when the valves float, kinda like hittin' a rev limiter, 40mm roundslide is to small for a 1000cc's IMO. the fact that you said the slide was sticking open from the vacuum is good sign it can't get the air it needs. it running better with a smaller main jet is another sign it can't get the air/fuel mix it needs. A 1000cc Sportster engine won't roll up on anything smaller than a 42mm roundslide Mikuni.
Ya need to get a tach so ya really know what your spinnin' but the stock valve springs will run @ 4K without any problem. if it feels like your sticking your hand over the carb @ 3/4 throttle then its runnin' outta air

[Nubs]

once you get it to breath right this is a great little add-on to tweak it in on the fly



Thunder Products - Performance carburetor and clutching for snowmobiles, motorcycles and ATVs.

[Hollywoodc]

That sounds like its right about what you said, like im covering the carb at 3/4.

Maybe I'll take the carb to my buddies machine shop and bore it out to 42mm and give it a shot.

I'll keep you posted. Thanks Nubs.

[Hollywoodc]

Offset Bored the carb to 42mm today.
Put a 170 main in and a 45 pilot.
Still bogging down at 3/4 throttle but the plugs show the rear cylinder on the slightly rich side and the front on the lean side hot, white ceramic.

It's gotta be the valves floating I'm thinking!
I'm gonna add the other set of shims that Al hodge sent me. He sent me (2) sets of .060 shims. He said to add one set and adjust it to .003.
But I may need 2 sets.

We'll so much for riding tomorrow. Back to the garage.

Update: I noticed today that the engine is Bogging down at only Half throttle, not 3/4. There is still alot more to go on the pedal.
So would this mean its a Needle issue?

My Buddy is a seadoo mechanic and he told me about a Digital Tach they use on them for about $35. Im gonna look into them tomorrow.

[Hollywoodc]

So I got it finally figured out!
I was way off on the jetting.
I searched for vm mikuni set ups on Sportsters to see what jetting they ran.
300 main is what most run. I was told to start with a 180.
The biggest jet I had was a 280, so I gave it a try, no more bogging down.
Checked the plugs and they were still a bit lean.
I'm gonna try drilling a few out to 290 and 300 and see how it feels and looks.

[Hollywoodc]

This is my first time feeling this engine with the mods I made.
I have to say, Im really impressed on how good this little engine feels. No problem drifting around the corners now!
Its gonna be perfect for the buggy once its dialed in.
Thanks for your help guys!

[Hollywoodc]

Ok, So before all the mods, Top speed I was hitting was 30MPH.
Did some jet changes today and my buddy did a side by side drive down a long street by my shop in his f250 Van, maxed out at about 50MPH! Nice!

This VM Carb didn't come with an Air jet so Im having difficulty finding the mid range on the Pilot screw so I have it set at about 2 turns out and adjusting the idles screw till it sounds good.
Im sure I can get a bit better takeoff once I get an air jet. Plus I could try going down a size on the Pilot also.

Now for the confusing part, so yesterday I tried the 280 and it looked Rich. Biggest jet I could find today was a 290, So I picked it up just in case.
I went to my neighbors machine shop and we measured the the 290 and he gave me to drill bit sizes bigger so I could drill out one of the 155 or 160 that I had.
I drill both out and still got Lean readings on the carbs. No more Bogging out but it sure is guzzling gas thats for sure.

I looked up the VM series carbs used on Sportster 1000's, they use a #30 Pilot and #300 Main.
Im thinking Im close to a #310 now with the drilled out jet and it still looks like its lean.

Granted, the VM Carbs for the sportster are 38mm, mine is bored out to 42mm.
I guess Im gonna have to find some bigger main jets.

Here are some pics of the Plugs from the last drilled out jet, which was .061in./1.57mm.


Cutaway

[Hollywoodc]

Mounted up an Equus 8068 Tach yesterday on the 35HP Vanguard. It has the Inductive Spark plug pick up. Didn't work at first but on the trouble shooting section it says to try reversing the direction of the pickup. Works pretty good now. It has like a half second delay but nothing to complain about.
Bought it at Oreillys for about $90 and its fairly easy to wire up, as long as you don't already have a mess of unecessary wires under your dash. I really need to go through the harness and consolidate it to only what is needed.
But all and all it seems to work ok with the inshop test.
I also ran wires to mount a cheapy Horn that i had sitting around. Last time we took the buggy to Dumont I kept thinking, I wish I had a horn to tap and signal my buddies when I was about to pass them on the outside or inside while riding the wall of a Bowl.

Now that I have the Tach, I can get the tuning down better. It sounds like 5000 RPM is right about where it will be Maxing out, can hear a slight ping right about 5000 so I don't think I want to go beyond that. Better then the Original 3600 rpm with governor.

https://www.youtube.com/watch?v=SbC1MjkFi2Y

[Hollywoodc]

Okay, so I went and get another set of Brand new Plugs.
I went with the Autolite Double Platinums at about $5 each compared to the regular Autolites at $3 a piece. Wanted to see if there would be a performance jump.

I have been driving all over town accumulating jets from various Moto Shops spending about $4-6 bucks per Jet!
But I found out a place about 5 miles from my shop that has pretty much every Jet and sells them for $2.50 each!!!

So I picked up a few more in the bigger Main range to try with the new plugs. Drove the buggy a few blocks over to an Industrial St. that has a good 1/4 Mile straight run. I changed the Plugs to the new ones once I got there. had my buddy in the Pass side and another buddy pacing in his truck.

Started with 20 Pilot and 350 Main.
Ran it up and down the street about 3x making sure I ran it at WOT. Plugs looked brand new still!

So I went back to the shop and changed out the Jets. I didn't have anything bigger then 350 which is about a 1.40mm Drill bit, so I drilled another jet to the next Drill bit size I had which was about 1.70mm. So im calculating that Im at about 420 by now. The VM Hex jets go all the way up to 660.

So now Im using a 30 Pilot and 420 Main.
I did a few more runs and read the plugs again. Top end feels good, just keep on going.
The front Cylinder is on the Left, which is starting to look Richer then the rear.
The 30 Pilot is looking a bit Rich on the plug ring so Im thinking of trying the 22.5 Pilot that I have next. Still a bit lean on the Porcelain for the Main.
Im thinking Im gonna need to go up more on the Main to about 450+.

The new double Platinum Plugs are easier to read then the cheaper ones because the threads are Silver. The cheap ones have black threads.
Well once I get this 42mm figured out, I'll at least have enough Jets to tune the 40mm. This way I can use the 40 for the Dunes and the 42 for the hard pack desert Long distance runs.

Heres a pic of the Plugs. How do they look to you guys?