Mr.modified's GTR Four Zero

cuz ur bad and not as skool 4 kool as mr. moodified.

Also if it does circle track it might add more oil to that side of the engine. Shouldn't matter much in a stock bore engine I wouldn't think.

Except the engine will be parallel with the tractor, but neat idea. I was going to make a gravity feed oil cooler/filter, but decided to use the aluminum finned side cover instead. I was going to weld a scoop on the inside of my steel side cover with a tube to the outside. Then run a rubber line or steel to a cooler or something and end up at one of the drain plugs. You could drill out one of the plugs and weld on a tube or tap the hole for a steel line.

In other news, the intake manifolds are 90% done. Throttles and return springs are figured out. Just working on how to link the chokes. Also I have the pull starter pulley ready and painted. Only a couple more small things and I should be able to test run the engine. For testing I think I'll have to run both throttles by hand which isn't perfect, but mostly I just need to get the idles close and get a start on setting the mixture. I imagine getting it to work right might be a little tough.

Couple of pics of what holds the suspension mount. This is almost the only place to run these tubes with all the steering rods in the way. Also, the steering pivot bolt will help hold it in place. Just need to weld a plate on top with a 1/2" hole.




The pull starter and flywheel bolted on.


A view of the throttle setup. Adjustment for matching up the two carbs will be at the gas pedal. Each separate cable will have it's own adjustment.

Neat throttle deal.

With mine the outter cable "shell" Black part or whatever comes out of the little socket on my throttle or whatever. I imagine theres a way to fix it, but maybe if you found a way you could do it now so that its not a issue.

Thanks. I think the throttle cable should be ok. Should stay put as long as it's adjusted pretty close.

I have the intakes finished. The string between them is the low tech choke linkage. For starting, you'll just pull a loop on the end of the string and hook it in a holder at the left carb.


Painted the intakes high heat aluminum. The choke string stays up and out of the way of the throttle cables and return springs. You can see the two tubes on this manifold for the throttle cables. The lower one goes to this carb, the top one is a guide for the cable which leads to the other carb.


Air filter bolted on.




Steering rod that will run along side the engine set in place to see how it lines up. Next I'm going to try making the transmission mount and maybe link it into the center axle bearing support. There's a slight issue with the air filter on the front cylinder being close to the wheel if the wheel is turned to the left when the suspension is compressed at the same time. I'll have to see how bad it is and decide what to do once I bolt on the second carb.

Looks really smart with that white shroud!
How did you bolt that blue starter pulley to the flywheel?

Four threaded holes are in the flywheel for bolting the plastic fan onto the flywheel. The pulley sits on top of the crankshaft. I put the bolts through the pulley with nuts threaded on under the pulley. With the bolts tightened down on the pulley some, then you reach under and tighten the nuts down to hold the plastic fan.

Purchased some 1/2" threaded rod which now holds the steering and also holds the suspension. Welded a plate on top of the shock mounts.


3/4" box steel welded across the frame. Transmission mount plate will be bolted on through the mount holes. Support for the center axle bearing welded on. This will be tied into the trans mount somehow, but I couldn't just run it right up under it because the trans pulley is in the way. The brake and drive gear will be on the same side of the axle. The transmission is over on the left side so there is room for the clutch as the slack side of the belt is on the right. It's tough to fit everything because we have to leave some room for the exhaust and also at some point the gas tank. I think I have things figured out now for the most part. With the trans location locked down, everything else won't be so bad to figure out. I think the toughest part is pretty much over now as far as fitting things in.

I am watching and learning at the same time. Looking good.

Thanks. Some good news, tonight I bolted on the second carb and the second air filter. With the front wheels turned all the way to the left (back of the left front tire closest to the air filter of the front cylinder) there's plenty of clearance. Even with the wheels turned all the way, there's room for about an inch or more of suspension travel. You shouldn't ever have the suspension completely compressed with the wheels at full lock anyway, unless your in the process of crashing into something. So, looks like the air filter has enough clearance and isn't a problem. Which is pretty good, since it would be tough to change around. I think all the things I was worried about fitting in should be ok now. A couple things might still be a little tight, like the exhaust or fuel tank and lines. But there should be enough space to work everything in. I think I should be able to get it finished in time for the cut-off. The body panels is what i'm mostly worried about. I think they will probably end up being smaller than I originally imagined. For instance, the carbs and air filters stick out pretty far on the left side of the tractor and your leg is going to have to be pretty close on that side. Most likely the hood isn't going to cover the whole area. Guess we'll see.

Thunderdivine wrote:

Where will you sit, on the axle or behind? now you realize how cramped it is for room

I'm going to put the seat as far forward as I can. Yes, things are extremely cramped! But that's part of what will make the finished machine neat to look at. This weekend I'm working on finishing the steering. With the steering and transmission mounted, then I can see how the seat will fit. I have to figure out if I'm going to mount the seat on some kind of springs or just bolt it solid.

A look at the dual carbs and mostly completed engine.


The rear air filter is going to be a bit close to your leg, but I think it should be workable. A couple of aluminum signs sitting just behind the rear axle will end up as the skid plate. I was going to use some thin aluminum I have, but with less than half inch of clearance between the skid plate and the pulleys, one hit on the bottom and things would be grinding. 1/4" bolts around the frame will hold the plate to the bottom. The signs aren't long enough to reach the whole length of the frame in one piece so it will be in two separate pieces.

That's a nice looking engine. Are you going to put side bars on like an outlaw car or foot pegs for your feet.

Thanks! I don't think I'm going to have any rub rails this time, but there will be either foot pegs or pads. Maybe a sort of skeleton setup made of rods.

Quite a bit of the steering column parts got finished this weekend. This is the washer that the steering wheel bolts to and the upper bushing. Bushing will unbolt so the shaft can be removed.


Lower bushing and 1" box steel brace that goes across the frame. I'll either bolt it down or weld it to the frame. Rod that goes to the front steering not yet cut to length in this picture. Arm isn't welded to the steering column yet.


Steering rod cut to length and welded back together. It more or less just worked out that there is just enough room to run the steering between the exhaust and engine block. Super close fit up front too with the bolt that hold the front joint only about an 1/8" away from the coil spring.

Still making up the body pannels to plan?? No big changes you think

redlinemotorsportts wrote:

Still making up the body pannels to plan?? No big changes you think

Well yeah, but mostly the rear is all I had figured out anyway. Probably the rear will be cut out around the seat. Not 100% sure if the front fenders will be part of the hood or not. If not, then maybe just thin plastic for the front. Mud flaps for the front tires as well as the rear because your feet will be right behind the front wheels. Headlights close together behind the grill most likely.

Steering completed except the upper steering column support. Here we see clearances at the front. Just fits between the shock/spring and the suspension mount.


From the rear looking forward. Steering arm welded on the column. Steering rod just fits under the exhaust. Probably should have waited to make the exhaust until last. But It doesn't make much difference, It's pretty close to where it needs to be anyway and everything clears.


Center bearing holes drilled. Gusset welded in between the center bearing support and the trans mount. Tacked the sprocket in place on the axle.


How things sit as they are now. Steering is quick, but fairly easy.

Awesome man. I gotta get to work on my build-off stuff, but seeing yours I kina get discouraged since yours is much more awesome.

Thunderdivine wrote:

Nice!
Hows the throw on the steering? Might wanna shorten the steering whhel arm part for less throw and better exhaust clearence.
Why is the engine sideways

Steering is quick but not super hard. I tried for a 1-1 ratio but It amounts to being just over that. If there's too much feedback when driving I'll shorten that arm as much as I can but there's only so far you can go before the steering rod runs into the engine block. I want to try it this way first and then If needed I can just unbolt the steering column, shorten, and repaint. I'd have to cut and weld I think because I think the most you can move it is not enough space to drill another hole. (Half hole width maybe). As for the engine mounting, I thought that would give you more room for your legs to fit around it, but with the manifolds, you barely break even on that idea. I don't know, I still think it's kinda neat to have it length wise in the frame.

LAWN MOWER MUDDER wrote:

I am drooling looking over these pictures... That is just fricken awesome dude...

Thanks, trying to keep it looking as professional as possible and not cut too many corners due to laziness. I think it's coming out ok so far.

1997 Murray wrote:

Awesome man. I gotta get to work on my build-off stuff, but seeing yours I kinda get discouraged since yours is much more awesome.

Thanks. No need to get discouraged though, the more stuff you work on the more ideas you get for things. For instance this front suspension with the a arms going straight to the heims only allows for a small amount of travel because the joint turns sideways and will hit the brackets. In this case it doesn't matter all that much because I only wanted 1-2" of travel anyway. I could have made some kind of jig to hold the shock mount too because it got bent out of shape some during welding.

Today at GTR Technologies...we dig out the high tech pipe bending equipment. Bent up some super light duty half inch electrical conduit to hold the upper steering column bushing.


Mocking up where the seat will be. Seat sitting on a 2x4 on top of the peerless 700. Still trying to decide if I should mount on springs or solid. There's a lot of work to be done on this in the next few weeks and things need to be figured out quick.


With the seat right here, my legs fit ok around the engine and clear everything pretty good. Seat will be sand blasted. Not sure on color. Either white, black, or blue to match the pulleys.


The conduit steering column support. This will have another tube (thicker wall) center where the steering column bearing is down. Also, I'm working on an aluminum firewall from more street sign material. The firewall will do three things. Keep the thin tubing from flexing, keep engine heat away from the driver, and hopefully slow pieces of an exploding flywheel down just a bit. Notice how close the exhaust pipe is in the lower left corner of the pic.


Close up of the exhaust clearance where I peened in a spot in the conduit so the exhaust doesn't vibrate against it. When everything is finished, you should be able to get both cylinder heads and all manifolds off the engine without taking the engine off the frame.

Got the firewall installed. Welded nuts to the 1/2" conduit. Had to file out a couple of holes after I drilled them in the firewall, but I got it to fit pretty good. I'll need to cut holes for a couple things like the throttle cables.


Getting ready to weld in the support tube. I think it's 16 guage, probably not quite twice as thick as the conduit.


Where the support tube connects to the steering bushing.

Cant wait to see this thing upstate.