Grand Daddy build

[Mballen13]

First time poster. Have been enjoying reading and learning on the forum. Decided to build an off road go kart for my farm. As this is my first kart I decided to get the Grand Daddy plans from spidercarts rather than designing from scratch. Haven't seen a completed build of the Grand Daddy on this forum and thought I would try to share my progress along with changes I make to the plans as I go.

Seems the Grand Daddy plans face many of the same issues regarding front steering/suspension geometries as the Arachnid. I have worked out the issues on paper and will see what happens as I build the chassis.

Will be using a modified Predator 212cc motor with this build. Using a Comet TAV2 torque converter. 6:1 gear ratio. Lots of other goodies will be unveiled as the project progresses.

Pictures will be posted as I progress. Will need to figure out how. Have seen several how-to's on the forum and just need to re-read once I have pictures to post.

Please feel free to critique and ask questions as the build progresses. I see a lot of projects that get started and either they don't get finished or the OP doesn't update their build log. I will be completing this project and will try not to fall victim to not updating the thread on a somewhat regular basis. This is a winter project and I will be working on it as time permits. Hopefully this weekend I will have the main subframe completed.

Thanks!

 

[machinist@large]

Welcome to the forum!!!

Please keep us in the loop. Lot's of pictures is even better!!! I can personally confirm that at least 3 different ways of uploading photo's have been well documented; displaying them as thumbnails appears to be the most popular with most members. Hardware issue's would need to be dealt with in/on a case-by-case basis.

Like I said before, welcome to the forum!!

 

[OzFab]

This is how most of us post pics.

Feel free to ask any questions as they arise.

Welcome to the forum.

 

[souperman000]

Welcome!

There was one granddaddy being built on here not too long ago. I don't believe it has been finished yet. Why not trying a search for it? It might have some good info.

 

[Doc Sprocket]

Welcome to the forum! We look forward to your build, and will help in any way we can!

What mods have you done to the engine?

 

[Pocketrocket]

Welcome to the forum!
Can't wait to see this finished ^.^

 

[Mballen13]

Souperman000 - Saw that someone started a build and am following the thread. Thanks!

Fabroman - Thanks for the links for posting pics. I am in the process of welding the subframe and building the motor. Will post pics Sunday.

toystory_4wd - Mods include Arc rod and flywheel, governor removal, oil pressure sensor removal, 18 lbs valve springs, re-jet carb with #90 main jet, gx140 E-tube, chome moly push rods, .016 copper head gasket, 4 degree timing advance key, grade 10.9 studs and bolts for head and side cover, header, and free flow exhaust. I think that is about it.

Thanks for all the interest and appreciate the offers to assist when in need.

 

[landuse]

Welcome to the forum

 

[Mballen13]

Nothing photogenic yet. Waiting on some misc parts for the motor and have the main sub-frame all tack welded. Of note for anyone building the Grand Daddy - I added 5 inches to the length of the main subframe. I am 5'8" and the addition of 5 inches seems spot on. Would be a bit cramped otherwise.

Progress will be slow until this weekend when I plan to put in some hours.

Stay tuned

 

[DaiSan76]

Nothing photogenic yet. Waiting on some misc parts for the motor and have the main sub-frame all tack welded. Of note for anyone building the Grand Daddy - I added 5 inches to the length of the main subframe. I am 5'8" and the addition of 5 inches seems spot on. Would be a bit cramped otherwise.

Progress will be slow until this weekend when I plan to put in some hours.

Stay tuned

When you get to it could you do some pics of the engine build and setup please?

 

[Mballen13]

Working on this go kart with my son has been a joyous and educational experience. I am posting several pictures of our progress.

DaiSan76 - Motor has been sealed up, however I have posted a pic of the motor. Still waiting on valve springs and need to plug the oil pressure sensor hole (got wrong size set screw). Otherwise motor is almost complete.

Changes from original GrandDaddy plans thus far:

Steering block width increased to 13 inches due to rack and pinion I am using. A-Arms will also be modified to ensure no bump steer.

Main subframe was increased in length by 5 inches to accommodate adults.

Rear subframe was also increased by 5 inches to ensure motor fit with torque converter. That didn't work as I have clearance issues! will have to fabricate motor mounts...live and learn!

Still have left to do:
-Finish welding chassis
-Make mounting brackets
-A-arms
-roll cage
-test fit all parts prior to paint or powder coat

I think that is all for tonight.

Please let me know if you have any comments, critiques, or questions. Please don't knock the welds, I am learning as I go!

 

[DaiSan76]

Is that the stock carb?

 

[Mballen13]

Is that the stock carb?

Yes, re-jetted with the gx140 E-tube.

 

[DaiSan76]

I've been kicking around the idea of ordering one of these to try and put on mine.
http://www.bmikarts.com/item/Carburetor-for-GY6-90cc-Engine---Used-713.001_used-7353
You seem to know allot more about small engines than I do, you think it would work?

 

[landuse]

Thats coming along nicely. It is funny how everybody lengthens their karts from what the plans always state. Everybody does it with the Arachnid as well. Don't the R & D folk realise that the frames need to be longer?

 

[Mballen13]

I've been kicking around the idea of ordering one of these to try and put on mine.
http://www.bmikarts.com/item/Carburetor-for-GY6-90cc-Engine---Used-713.001_used-7353
You seem to know allot more about small engines than I do, you think it would work?

A little background on myself. I learned tuning theory with fuel injected motors. Fortunately those same theories apply with carbureted motors, however instead of tuning with a computer you are mechanically adjusting air, fuel, and timing.

While I am not completely familiar with the carburetor you have linked, I doubt it would work on the predator without fabbing some sort of mount as it does not appear it is a direct bolt on. That is from a GY6 motor which is an altogether different platform. Also if you are looking for performance gains this may not be the best route to go as it was made for a 90cc motor and would most likely flow less fuel. Typically for performance gains you would want to get a bigger bored carburetor for more fuel. I am sure someone with more knowledge can chime in and correct me if my educated guess is wrong.

Hope this helps.

 

[Mballen13]

Thats coming along nicely. It is funny how everybody lengthens their karts from what the plans always state. Everybody does it with the Arachnid as well. Don't the R & D folk realise that the frames need to be longer?

Agreed, they at least need to put a disclaimer in the plans that the dimensions are for a child and not an adult. I will say that having the plans has made this process more enjoyable. I am not an engineer so drafting my own plans would have been problematic. I am changing as I go, but that is a lot easier than re-creating the wheel!

QUESTION - I read this regarding charging systems - http://atvconnection.com/articles/a-primer-on-atv-charging-systems-2/ - Seems the lawn tractor and ATV alternators don't rob too much power and may potentially add significant convenience. Thoughts? I plan to run a 2000lb winch and some low wattage lights.

Have a look at these small alternators - http://www.jackssmallengines.com/Alternator/John-Deere/Utility-Vehicles-Utv/A

 

[Mballen13]

Bolted the motor together, put fluids in it, and was having fueling problems and it wouldn't start. Unbolted the tank to better allow fuel flow and she fired right up. May need to consider a silencer as it is VERY loud with just a straight header.

Hope to finish up all the welding this weekend and have a rolling chassis. Pics will surely follow if I get that accomplished.

Sitting here thinking if I needed to update anything else and my ears are ringing. Any suggestions for a silencer?

Also looking for input on why I had to unbolt my tank to allow for more fuel. Fuel lines are routed the same as they were originally. Really don't want to have to either relocate the tank of add a pump and new tank.

 

[DaiSan76]

Bolted the motor together, put fluids in it, and was having fueling problems and it wouldn't start. Unbolted the tank to better allow fuel flow and she fired right up. May need to consider a silencer as it is VERY loud with just a straight header.

Hope to finish up all the welding this weekend and have a rolling chassis. Pics will surely follow if I get that accomplished.

Sitting here thinking if I needed to update anything else and my ears are ringing. Any suggestions for a silencer?

Also looking for input on why I had to unbolt my tank to allow for more fuel. Fuel lines are routed the same as they were originally. Really don't want to have to either relocate the tank of add a pump and new tank.

May have been something kinked. You could just add a washer under each of the three bolts if unbolting it was all it took to let the fuel flow.

 

[Mballen13]

May have been something kinked. You could just add a washer under each of the three bolts if unbolting it was all it took to let the fuel flow.

Fuel line re-routed and don't seem to be having any issues. Thanks for the suggestion however no washers were necessary.

A-Arms tacked. Need to make brackets and buy hardware to get into a roller. Pics should be posted tomorrow.