From what Dale told me the triple stator plate bolts right into the cast case. Yes you should be able to advance the T-cat ignition with both offset timing key and slotting the pick up sensor. I have done both of those on race T-cat engines and its pretty easy.
Old school, big power
- Thread starter mattymac
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From what Dale told me the triple stator plate bolts right into the cast case. Yes you should be able to advance the T-cat ignition with both offset timing key and slotting the pick up sensor. I have done both of those on race T-cat engines and its pretty easy.
So you are saying you need to use the ZR aluminum stator mount plate and bolt the triple stator on to it when using the ZR case's that are welded together??
shoe horn
It will take a special shoe horn but with what I have planned I am sure it will fit. This,
has been a lot of thought and measuring. The hood will be highly modified as will the rest of the chassis. Mind you, I am no fab pro but, I know a few and in the end there really won't be that much in the way of specially built parts, three I think. I will be using cat parts from a few generations mostly, and one or two aftermarket parts, nothing major. Or, cat design modded to fit my needs. Measure three ways cut once.. It will fit.... I am not in a hurry to build so I can get right.
It will take a special shoe horn but with what I have planned I am sure it will fit. This,
has been a lot of thought and measuring. The hood will be highly modified as will the rest of the chassis. Mind you, I am no fab pro but, I know a few and in the end there really won't be that much in the way of specially built parts, three I think. I will be using cat parts from a few generations mostly, and one or two aftermarket parts, nothing major. Or, cat design modded to fit my needs. Measure three ways cut once.. It will fit.... I am not in a hurry to build so I can get right.
I wouldn't recommend offset keys, since there's already potential for shearing the key. Making the key even thinner I don't think is a great idea.
Yes. I assume the cast one is the same way. I'll find out soon, we did buy one.
Looking forward to seeing it! The only newer chassis I thought might work is an IQR, but I think you'd have to use a gear drive to move the brakes out of the way.
Me Too!
Ya, love triples, not a fan of the tech stuff too many band aids and all it takes is a little water to ruin your day and bank account. It's great for those who can make it work.
A question I have about this engine is, is there any more security of a mid range
lean spot? I have an idea of a possible fix just not sure if it can be accomplished
because the jet needle is so small.
Ya, love triples, not a fan of the tech stuff too many band aids and all it takes is a little water to ruin your day and bank account. It's great for those who can make it work.
A question I have about this engine is, is there any more security of a mid range
lean spot? I have an idea of a possible fix just not sure if it can be accomplished
because the jet needle is so small.
We haven't had too many problems. The mid-range lean spot isn't really a lean spot, it's hot timing. I imagine that's mostly fixed actually with the T-cat ignition. I've thought about having a couple degrees of timing taken out in the mid when we're doing our custom programs.
If any one of you guys are going to port your case there is power to be had. In CC volume the ZR8/9 is low in crankcase volume. I have access to a few old ISR factory specs sheets. To give you a idea on crankcase volume...
Crankcase Volume with 1 piston at BDC & entire crankcase filled.
2000 T-cat = 2070cc / 3 X 2 = (if it was a twin =1380cc)
03 F7 = 1712cc
ZR800 & 900 = 1111cc
If you were a triple guy before you know how well the T-cats responded to tunnel porting while adding crankcase volume.
Crankcase Volume with 1 piston at BDC & entire crankcase filled.
2000 T-cat = 2070cc / 3 X 2 = (if it was a twin =1380cc)
03 F7 = 1712cc
ZR800 & 900 = 1111cc
If you were a triple guy before you know how well the T-cats responded to tunnel porting while adding crankcase volume.
been elk hunting, heres some good info in thundercat/zrt ignitions:
part 1
https://www.youtube.com/watch?v=6GriY9zwyUw
part 2
https://www.youtube.com/watch?v=O0q4_3kWCWI
good info!!! The older tcat cdi's arent programmable, they are hard wired inside and potted/sealed. The newer twin cdi's have a plug going into the box and they are programmable.
part 1
https://www.youtube.com/watch?v=6GriY9zwyUw
part 2
https://www.youtube.com/watch?v=O0q4_3kWCWI
good info!!! The older tcat cdi's arent programmable, they are hard wired inside and potted/sealed. The newer twin cdi's have a plug going into the box and they are programmable.
as far as running offset keys and shearing them... the problem isnt the key itself! The key is only there to index the flywheel to insure correct timing when assembling. If the taper between the flywheel hub and crankshaft is correct technically you dont even need a keyway to keep it in place! (think about your clutch/pto end of the crank!) THE TAPERS ARE DIFFERENT BETWEEN THE TCAT FLYWHEEL AND TWIN MAG CRANK END!! extremely close but not correct!!!
P
Fix
Is there enough meat on the carb end taper to machine to fit the t-cat taper flywheel? Or machine a efi taper to fit the t-cat flywheel?
Is there enough meat on the carb end taper to machine to fit the t-cat taper flywheel? Or machine a efi taper to fit the t-cat flywheel?
EFI has a bigger end than the carb crank.
The problem with turning down the carb end is to get the flywheel to fit the carb crank setup wont work. (going from to small to even smaller)
When the flywheel gets machined its gets set deeper into the case/crank... luckily theres only a few 10 thousandths difference so it doesnt have to go much deeper for a proper fit on the crank and will work just fine!
This is what we had problems with back in the polaris watercraft days in the late 90's having to re-taper and check the depth to get the flywheels to go on. But PAR (brad wursten) machined a new hub altogether to put in place since the polaris hubs were riveted into the flywheel which made this super easy! The cat flywheels arent like that.
turning down the EFI crank end is another way to go about it!
So, how wide over all is this engine with the drive clutch and mag cover on? I have to rework some bracing
and would like a head start on material...
and would like a head start on material...
Good Idea as long as the Mag end if off.
Sent this in a private message, but the triple with a 6 tower Cat clutch, and our recoil adapter with an M1000 recoil is 30.5" wide.
Stock recoil should be within tenths of the same.
Made some progress but ran into a snag... got it fired with the TCAT ignition and would only idle, wouldnt want to pick up rpm's, without having a spare tcat motor laying around to get measurements from, scott and I have come to the conclusion that the initial starting point of where spark occurs between the twin motor and the tcat is obviously different. When I re-keyed/tapered my flywheel I mirrored the twin key way position, what needed to happen was reclock the flywheel over to where the twin ignition pickup sensor is (which is what I did) but then account for the amount of degrees difference between where the mag cyl is at TDC, the trigger on the flywheel and the sensor is between the twin and tcat engines. Its an easy fix but something that was learned along the way... Parts are coming to remedy this, I will now be running a reprogrammed twin CDI box, twin stator, with the same tcat flywheel and coils.
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WOW!!! Nice work, can't wait to hear this monster, am very interested, hope I can build one of these with your help and some $$$... Still trying to justify using the 1000 twin but I don't like efi., seems limited. I have researched a possible way or two, to put carbs on this engine, both ways are not THAT complicated just one of those think it through situations, kind of like what what you going through with your build. I like the idea of more power from a mildly built triple with not that much more weight. When you can get 200++++ hp weight kind of fades away...
Not near as much as myself!
If I had a dollar for every one of my buddies that came in my shop that looked at this project that said the same thing... The first tank of fuel would be bought and paid for!
Next week this thing will pop for sure! I even got some extra timing tools to make sure that my timing is right where it needs to be!
Ill post a video of when it makes some smoke!
That really surprises me? Since Cat/Suzuki engineered the 8/900 engine from day one to be 1000cc's in factory form that the crankcase volume to be that low in comparison to these other engines??
Just goes to show how these motors respond so well to pipes/porting/big bores etc... they want to breathe!!!! All choked down with those small pistons!
And the F7, WOW! But there were more 700cc laydown motors in my area that were 800 big bores than 700cc's and they ran better but IMO didnt see the gains that a twin piped bored 8/900
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ok, this is what I have come up with on my motor as far as ignition timing...
I have two motors im using for reference, a standard 900 twin and the 1500 triple... Im learning some things as I go along so hopefully others can too! Figuring out ignition/timing curves is kind of a lost art anymore in two stroke performance but I think its HUGE when it comes to how a sled runs, and also why some sleds run better than others out of the box... When I had my tcat flywheel re-tapered/re-keyed it was measured by a machine that was accurate within less than .0001" the difference between one mass produced flywheel to the next was scary!
Just to give some measurements...
Here is the triple... MAG cyl at TRUE TDC, zeroed on the bore gauge and a degree wheel...
This is where at the same TDC, where my modded tcat flywheel trigger comes across the ignition sensor..
This scared me a bit, I was under the impression that it would be more toward the center... NOPE! BUT...
This is where the STOCK 900 is at the same TRUE TDC
Here is where the leading edge of the TRIPLE flywheel trigger hits the ignition sensor... Notice how many degrees I rotated the engine backwards to get the trigger to this point (4 degrees) yes it looks like more but the angle I had to take the pic at makes it look like like 5 you can also tell this flywheel has two flywheel keyway slots in it (modded tcat) Look at the welding rod "pointer" in relation to the degree wheel
Heres the twin in the same configuration, (no welding rod pointer just a sharpie, sorry) the angle of my phone was goofy to get this pic without getting any glare but its still at the same 4 degrees ATDC to intersect at the same leading edge of the flywheel trigger on the TWIN un-modded flywheel... I used the leading edge of the flywheel trigger as a reference since thats about the only thing similar between the two flywheels to use as a common measuring point between the two engines...
Now as far as static timing goes on the bench this is about as close as you can get... the true test is timing advance with a timing light at rpm so heres some timing marks (5 deg... have to make single degree increments still) on the clutch once this motor is spinning.
Since Scott has left this info in another forum I have done the work to bring it over to good ol' snowest!
Thanks Scott!!!
Now, to make the twin CDI work, at minimum it needs to be reprogrammed to make the RPM correctly correspond to timing advance since now were dealing with 3 flywheel triggers instead of two, (the CDI thinks 1000 RPM's is now 1500, 1000x's 1.5) So obviously an un-reprogramed twin CDI wouldnt have the correct ignition advance as RPM's increased. Scott has the answer to that along with some new timing curves to the original twin ignition timing curve itself! Ill let him comment on that if he wants.
Honestly Im hoping to be around the 14-16 degrees BTDC on this engine at the low 8000 rpm mark, Scott has sent me a re-programmed CDI that has an extra 2* of ignition advance at higher RPM's, the trick is going to be getting around the hot timing in the mid range the twins are known for but him and his dad have another curve they're working on to combat that issue as well!
I have two motors im using for reference, a standard 900 twin and the 1500 triple... Im learning some things as I go along so hopefully others can too! Figuring out ignition/timing curves is kind of a lost art anymore in two stroke performance but I think its HUGE when it comes to how a sled runs, and also why some sleds run better than others out of the box... When I had my tcat flywheel re-tapered/re-keyed it was measured by a machine that was accurate within less than .0001" the difference between one mass produced flywheel to the next was scary!
Just to give some measurements...
Here is the triple... MAG cyl at TRUE TDC, zeroed on the bore gauge and a degree wheel...
This is where at the same TDC, where my modded tcat flywheel trigger comes across the ignition sensor..
This scared me a bit, I was under the impression that it would be more toward the center... NOPE! BUT...
This is where the STOCK 900 is at the same TRUE TDC
Here is where the leading edge of the TRIPLE flywheel trigger hits the ignition sensor... Notice how many degrees I rotated the engine backwards to get the trigger to this point (4 degrees) yes it looks like more but the angle I had to take the pic at makes it look like like 5 you can also tell this flywheel has two flywheel keyway slots in it (modded tcat) Look at the welding rod "pointer" in relation to the degree wheel
Heres the twin in the same configuration, (no welding rod pointer just a sharpie, sorry) the angle of my phone was goofy to get this pic without getting any glare but its still at the same 4 degrees ATDC to intersect at the same leading edge of the flywheel trigger on the TWIN un-modded flywheel... I used the leading edge of the flywheel trigger as a reference since thats about the only thing similar between the two flywheels to use as a common measuring point between the two engines...
Now as far as static timing goes on the bench this is about as close as you can get... the true test is timing advance with a timing light at rpm so heres some timing marks (5 deg... have to make single degree increments still) on the clutch once this motor is spinning.
Since Scott has left this info in another forum I have done the work to bring it over to good ol' snowest!
Thanks Scott!!!
Now, to make the twin CDI work, at minimum it needs to be reprogrammed to make the RPM correctly correspond to timing advance since now were dealing with 3 flywheel triggers instead of two, (the CDI thinks 1000 RPM's is now 1500, 1000x's 1.5) So obviously an un-reprogramed twin CDI wouldnt have the correct ignition advance as RPM's increased. Scott has the answer to that along with some new timing curves to the original twin ignition timing curve itself! Ill let him comment on that if he wants.
Honestly Im hoping to be around the 14-16 degrees BTDC on this engine at the low 8000 rpm mark, Scott has sent me a re-programmed CDI that has an extra 2* of ignition advance at higher RPM's, the trick is going to be getting around the hot timing in the mid range the twins are known for but him and his dad have another curve they're working on to combat that issue as well!
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