Everything2Stroke Forum banner

1 - 20 of 32 Posts

·
Registered
Joined
·
18 Posts
Discussion Starter #1
so one of my best friends days picked a really rough zilla today for 700 buck off criagslist. it's an 87 zilla that is barney puple and sprayed other colors over it as well as a whit splatter. he sold it because it tossed him over the bars when it kicked back once. upon looking into it for him it is pretty rought shape. it runs but barily because it is missing big pieces of the reeds from each corner of the reed cage. it also needs the rear brake master and the the front handle because they put the wrong one on aswell as it has a keihin carb when it should have a mukuni. so looking past everything that is visably wrong and everything that make it a total basket case is a huge ray of light. we feel like the quad was raced back in the day and it has some parts on it to back that up but i am not really sure what i am looking at as to how good they are. the jug has no size stamped in it anymore and on one side of it are the letters srp and on the other side it says sundahl racing. i have looked it up but i can find a shee frames. the jug and head have been ported and polished and it has a pipe on it the dump's near the left front tire. any info on the jug and pipe would be much appreiated. thanks guys
 

·
Registered
Joined
·
1,066 Posts
Sounds interesting. Look forward to seeing some pics of it. CT racing used to sell a pipe for the zilla that dumped by the front tire.
 

·
Registered
Joined
·
18 Posts
Discussion Starter #4
yeah i will get pics up today and i figured the pipe was a ct. it's chrome plated and looks very similar to the one's i have seen on here
 

·
Registered
Joined
·
18 Posts
Discussion Starter #5
here is about what we started with


here is the right side of the cylinder


here is the left side of the cylinder


and here is the porting inside the jug


update. we changed the reeds and put working brake masters front or rear. i started it but didn't have hadly any compression and had next to no torque. next is gonna be putting a proper carb on it because the on they put on it wasn't right and then the owner needs to learn how to ride it before we rebuild the topend and tightin it up. were just at the start of this so we will see. any feedback on the motor or head is more then welcome because we want to build this thing to be fast but reliable.
 

·
Registered
Joined
·
6 Posts
Sundahl racing was owned by former team Honda member Dean Sundahl, one of the fastest desert racers there is. Used to build sick Banshees
 

·
Registered
Joined
·
18 Posts
Discussion Starter #7
thats all i have been able to find out about him aswell but what throws me is this is a lt500r and this name is cast into the jug?
 

·
Registered
Joined
·
18 Posts
Discussion Starter #9
thats kinda what i thought about the pipe to. the silencer tip is rotted and it has no core and there not to thrilled with the idea of it dumping premix on the peg so he is gonna be looking for a rear exiting exhaust once we can get the motor to run right
 

·
Registered
Joined
·
18 Posts
Discussion Starter #10
yeah. it's a little rough but our hope is to get it running for this season and then come winter it is gonna get completly torn down and gone though
 

·
Registered
Joined
·
330 Posts
any updates with the sundahl? want to see pics of the rebuild?
 

·
Registered
Joined
·
18 Posts
Discussion Starter #13
well we took the top end apart a few weeks ago and discoved the jug has a ton of port work done to the point that the outer wall of the jug is less the a mm thick but there isn't any sharp edges left anywhere. the sundahl was put in by hand with a dremel as well the srp on the other side. the ears have been welded and the intake side bolts have had huge spacers (about an inch, matching hieght with exhaust side) welded in and it doesn't use a normal but a shancked nut instead. i am not new to motor cycle as a whole but i am to zillas. is this normal? something else too. it has two sleeves? other then that it needs a piston and ring and were gonna go with the rm bearing and alum thrust washers. we have also scored at a local cycle salvage yard and found mint condition suzuki body, not mayers. were saving for a piston and ring and the old piston was cracked in about 7 spots and has about 1/4mm of loose play in it front to back and the wrist pin is so worn you can see wher it was startin to be able to contact the head. luckly we saved this fine beast when we did. pics to come soon after i see it next
 

·
Vendor
Joined
·
1,500 Posts
I was too polite to comment on the cylinder in my last post. Did you measure the bore for the new piston size?
The intake side of your cylinder looks as though a hacker got to it. The intake rib could break away at any time. A sleeve inside another iron sleeve is also very questionable. This would mean that the intake port rib is extra thin. As far as the port work goes, everyone with a grinder seems to think that the larger the intake ports the better, NOT SO. The intake ports should be proportionate to the reed valve area & the carburetor bore diameter.
If you pick up a copy of "Performance Tuning" A. Graham Bell, Everything is in there someplace for you to read about. Even if you farm out your work you should know what's going on.
I expect that Denny from Flo-Tek will throw in a comment in a few hours, He seems to be a more reliable porting shop on the east coast.
E2S The place to go when you need to know
:thumbsup:

On the side: Just because there is a bunch of grinding done on the cylinder doesn't mean that a proper port job has been done. 3 things make the bulk of the difference in port work.
1. Port heights & Blow down timing. It's not really necessary to find someone with a high powered Woop-T-Doo porting program. Just someone who understands what power band your going to use while riding.
2. Deck heights & squish, compression, i.e. head work
3. A Pipe which talks to your port heights.
IMO

I don't know who's pipe work is best, that's for other readers to comment on. Sorry for being so long winded, this short lecture needs to be paisted in most every day.
 

·
Registered
Joined
·
330 Posts
ive never heard of a sleeve inside of another sleeve, was this done becase the first sleeve was cut to big and got to wide to repair? rather than replaced it they just bored it bigger and slammed a smaller sleeve in? whats the bore size?
 

·
Registered
Joined
·
18 Posts
Discussion Starter #17
when i said that the piston was undersized. i was referring to the one we took out, it was worn down not undersized from being the wrong bore. i measured the bore at 86.5 and the piston at the piston surface just above the wrist-pin was the same where as if i measure the intake/ exhaust surface it is 85.9mm. as for the second sleeve i am not sure right now why it is there yet but were gonna go with it, and the port was well thought out and done. it's not my quad personally but i have some pull with it, the carb is a keihin 39mm with a sudco tag say for track use only. but that is gonna change to the pwk 42mm keihin. other than that were gonna start with a simple flat hone and throw a piston in it. there's not much scaring in the cylinder and the bottom end is tight.
 

·
Vendor
Joined
·
1,500 Posts
Where your measuring and the bottom is tight? You measure the piston towards the bottom perpendicular to the pin at the largest diameter. None of us are giving you a bad time, only trying to help. A simple Flat hone & throw a piston in it? Hold your horses & use a dial bore gauge. If you read the first few pages of "How it's Done" everything is accurately explained. The porting aside, the piston to bore fit is the heart of your engine. Seems like you need a little more study. :NodYes:
 

·
Registered
Joined
·
18 Posts
Discussion Starter #19
i am sure you are just trying to help. srry i sound defensive and like i haven't put the time in this thing because thats not the case. it (the quad)really is a bc but has alot of petantial. we measured the piston right near the face and various points down the piston both perpendicular and inline with the pin and the 86.50mm on the money was measured just above the pin and was the largest point on the piston and the sleeve measured the same. by bottom is tight i was refereeing to bottom end of the motor the crank and rod bearings feel very good and have no grittness or slop. other then the piston the jug and bottom end of the motor seem to be in pretty good shape
 
1 - 20 of 32 Posts
Top