I've been searching the site for overhaul info, and I don't find it. Can anyone tell me a good source to get the gasket set, head gasket and oversized pistons and rings? My local auto parts store says they can get them, if I bring in the old ones. Sounds weird. I can buy from a couple of local shops, or order online. I ride my Eliminator to work daily, so I need to get it back on the road. Is there anyone in Kansas City that wants to help, or provide encouragement to get this done? I live up north of the river. I will begin teardown later this week.
zlMark
Cult Leader
Check with John in the zl store to see what all he can get. he should be able to supply you with everything.
I wouldn't do this without upgrading the starter clutch at least. There's also oil mods and starter chain upgrades to do as well
I wouldn't do this without upgrading the starter clutch at least. There's also oil mods and starter chain upgrades to do as well
Scoobys_piece
Senior Member
Be careful! Those holes are real close to the water passages. Recommendation...Go with forged pistons and ZERO Gap rings. Will raise the compression, without boring. Just my two pennies...wait..hold On..I need those...I gotta get a B-King!
Also, think about slappn on a bigger head that will mate to the block.
A bigger head like a zg1000? Or will a larger head fit? I am mostly wanting a dependable bike and I don't have a lot of time to search for parts, but I will take a quick look around before the overhaul. It's always started great, maybe the starter mods have already been done. It had 14,000 miles when I bought it. a couple of years later and it has 24,000 on it now. I will get with John for parts.
I have a second zl900 but build for a fun hot rod bike...... right now I'm missing my daily bike!
I have a second zl900 but build for a fun hot rod bike...... right now I'm missing my daily bike!
The zl store is somewhat confusing to me. I didn't see how to find prices, and the link to the price request form is broken from my location. What I need is to know what to order: crank bearings, rod bearings, Wrist pins? Head gasket. I am hoping many of the gaskets can be re-used to save me some expense. I will have to split the case to do the crank, so I'm guessing a gasket for the split case.
Are there any non OEM gasket sets that will work, but are cheaper than the factory gaskets?
Things I need to do:
Drain oil.
Remove engine from bike. "I hear this is very difficult".
Pull the heads and cylinders off of the engine.
See if I can determine where the knocking is coming from.
Check for scored cylinder walls.
Mark pistons and rods and remove pistons from rods.
Mic everything.
Hone cylinder walls.
install new bearings where needed.
Install gapless rings.
install pistons on rods, and re-assemble top end.
upgrade starter chain and clutch.
Are there any non OEM gasket sets that will work, but are cheaper than the factory gaskets?
Things I need to do:
Drain oil.
Remove engine from bike. "I hear this is very difficult".
Pull the heads and cylinders off of the engine.
See if I can determine where the knocking is coming from.
Check for scored cylinder walls.
Mark pistons and rods and remove pistons from rods.
Mic everything.
Hone cylinder walls.
install new bearings where needed.
Install gapless rings.
install pistons on rods, and re-assemble top end.
upgrade starter chain and clutch.
Scoobys_piece
Senior Member
I don't know about fitment...I did swap my head on my GS1100....but it's been 25 years ago and can't remember..age...
I would go with forged pistons and zero gap rings. Swapping heads, can be challenging....it probably can be done, but I'm not familiar enough to make any tangible recommendations.
Good luck with whatever you decide...I'll be interested in your findins.
paulfun
"King Of The 1/4mi (Internally Stock)"
If you are posatively going to bore out the cycl and install the biger pistons then the only two things that you should be ordering ahead of time is a complete engine gasget kit and the wiseco big bore kit Othe things like bearings wrist pins exct will have to wait for the bike to come apart so you can determine what actually needs replaced. Bearings are of different sizes and without a tear down you wont know wich ones to order. And even if you did if a bearing is making a noise you might have to have something machined to correct its ill wear and that would also change the bearing size.
I wouldnt worry about installing gapless rings unless you plan on racing it. It dosnt add to the static compression as some belive and unless your pushing for the absolute last ounce of power the cost and install isnt really worth the cost or install time. All pistons for the zl are forged kits as are the stock pistons. If your purchasing a wiseco big bore kit the pistons will actually come with new rings, pins and clips.
My advice would actually be to tear it down and measure everything to determine what is wrong and what is in or out of spec before even considering if its worth rebuilding. You could probably find a complete low mile connie motor that you could install in a weekend and be done, for far less than the true cost of a total and correct rebuild.
If you cant find something on the zl-store web site use the contackt info and send john a message. He will help you find it or respond direectly with parts avail and cost. Just be surew to let him know your a member here.
PS Trying to re-use gasgets with a total rebuild isnt very smart and will probably prove to be more expensive and time consuming in the long run!
I wouldnt worry about installing gapless rings unless you plan on racing it. It dosnt add to the static compression as some belive and unless your pushing for the absolute last ounce of power the cost and install isnt really worth the cost or install time. All pistons for the zl are forged kits as are the stock pistons. If your purchasing a wiseco big bore kit the pistons will actually come with new rings, pins and clips.
My advice would actually be to tear it down and measure everything to determine what is wrong and what is in or out of spec before even considering if its worth rebuilding. You could probably find a complete low mile connie motor that you could install in a weekend and be done, for far less than the true cost of a total and correct rebuild.
If you cant find something on the zl-store web site use the contackt info and send john a message. He will help you find it or respond direectly with parts avail and cost. Just be surew to let him know your a member here.
PS Trying to re-use gasgets with a total rebuild isnt very smart and will probably prove to be more expensive and time consuming in the long run!
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Scoobys_piece
Senior Member
Swap and go......then you'll have a motor that you CAN wrench the hell outtaof."Swap and go" does sound like the cheapest option. I have a complete motor that I had planned to use on a project bike. It has water getting into the oil, so a possible water pump leak, or head gasket. I need to do a compression check on it, but it ran good. Maybe swap my water pump from my newly broken motor to this other one?
I will do the rebuild either way, because I want to build this project bike. The more I read about the wiseco big bore kit, it seems pretty good. I think I want to stay with the stock 900 engine. It has a bore and stroke of 72.5x55 where the 1000 has 74x58. I want to keep the shorter stroke. The "big bore" pistons for the 900 are 75mm(2.5 over stock) and for the 1000 75.5mm(1.5 over stock).
Calculations say a 900(55mm stroke) with stock 72.5mm pistons is 908cc
with 75mm pistons = 972cc, (64cc gain)
a 900 with 1000 cylinders and stock 74mm pistons = 946cc, (38cc gain)
a 900 (55mm stroke) with 1000 cylinders and 75.5mm pistons = 985cc, (77cc gain)
I don't know if the search for a 1,000 head is worth the extra 13cc.
Just for recording the facts here. A 1000(58mm stroke) with a 75.5mm piston = 1039cc, 41cc gain over the stock 998.
Is there any data showing the power output of a "big bore" 900 compared to a 1000?
Will my current carburetors handle enough airflow for 972cc?
I will do the rebuild either way, because I want to build this project bike. The more I read about the wiseco big bore kit, it seems pretty good. I think I want to stay with the stock 900 engine. It has a bore and stroke of 72.5x55 where the 1000 has 74x58. I want to keep the shorter stroke. The "big bore" pistons for the 900 are 75mm(2.5 over stock) and for the 1000 75.5mm(1.5 over stock).
Calculations say a 900(55mm stroke) with stock 72.5mm pistons is 908cc
with 75mm pistons = 972cc, (64cc gain)
a 900 with 1000 cylinders and stock 74mm pistons = 946cc, (38cc gain)
a 900 (55mm stroke) with 1000 cylinders and 75.5mm pistons = 985cc, (77cc gain)
I don't know if the search for a 1,000 head is worth the extra 13cc.
Just for recording the facts here. A 1000(58mm stroke) with a 75.5mm piston = 1039cc, 41cc gain over the stock 998.
Is there any data showing the power output of a "big bore" 900 compared to a 1000?
Will my current carburetors handle enough airflow for 972cc?
Scoobys_piece
Senior Member
Has anyone every tried swapping out cranks.... I'm a bowtie guy and the things that we did to get the small blocks to keep up with the big blocks was to either use a 350 block with a 400 crank=377, or a 400 block with a 350 crank=383. These conversions made a good amount of HP without breaking the bank. I would be interested in anyone ever tried this with the 900.
paulfun
"King Of The 1/4mi (Internally Stock)"
There is no need for a different head to do any of the big bore set ups you have described. The head gasget is the only determining factor. If I remeber correctly someone did a comparison and figured the 900 cyl can indeed be bored out to the big bore for the zl1 but dont qoute me on that as its been a long time.
The piston pin hieght and rod ratio(lengnth) are the next factors that you need to consider as they are different between the zl9 and the zl1.
The big bore kits from wiseco used to come with the apropriate head gasget for the kit, not sure if they still do.
The best cobination of parts using the older zl,zx motor parts in conjunction with the wiseco pistons made for them back in the day would be to use the zl1 or zx1000r crank, the rods from a zx1000r and the wiseco big bore kit for the zx1000r. The rods on the zx1000r are different from the zl1 and thus the piston pin hieght is different thats why they list different kits for them. The rod ratio does affect the power curve even with the small difference between them.
The piston pin hieght and rod ratio(lengnth) are the next factors that you need to consider as they are different between the zl9 and the zl1.
The big bore kits from wiseco used to come with the apropriate head gasget for the kit, not sure if they still do.
The best cobination of parts using the older zl,zx motor parts in conjunction with the wiseco pistons made for them back in the day would be to use the zl1 or zx1000r crank, the rods from a zx1000r and the wiseco big bore kit for the zx1000r. The rods on the zx1000r are different from the zl1 and thus the piston pin hieght is different thats why they list different kits for them. The rod ratio does affect the power curve even with the small difference between them.
Yeah that is what I though! Then the damn thing gave me issues...It's out again and awaiting funds to repair it.
Yup
It's possible, but you have to watch rod length, and piston pin height like Paul said.
I'm running ZX10b crank, rods and pistons.
The Rods are the same length as ZL900 if I recall correctly...But they are suppose to be stronger (not sure about that).
The pin height on the ZX10b pistons are different than that of the ZL1000 and the crank is different too.
I have homework to do, but I will be comparing the ZL900 crank to the ZX10b's when I build mine back up again.