Freestyle Trixstar, unknown freestyle build.

[BlackMerry]

Thank you all!
The 5mm plate compensates for the different distance between pin and top of piston. Nothing to do with stroke.
Still unknown what brand/type of cylinder and cylinder head are used. Cannot find anything on the internet which have the same looks as my head. Maybe one still recognizes it?

I bought a freestyle ski with the goal to backflip it. I know that a stroker engine gives more torque and thus more low-end required for flipping. I think that with this setup you can still flip it, but it will be much much harder.
Unfortunately, this setup is not the 1000CC (with stroker engine) which the previous owner told me.
The price I paid was based on the 1000CC setup. What would be the costs to still transform it to a close to 1000cc engine? I know that 10mm stroke requires a lot of adjusting to make room for the crankshaft. It will even need a stiffening plate at the bottom. But maybe someone can give me an estimation of the costs. Or is it better to stay with 8mm stroker to get the most bang for the buck and get the best performance without huge expenses on maintenance?

Next to this, maintenance. With the standard stroke there is less maintanance compared to a 10mm stroker engine. But how big is the difference? Maybe someone can tell something about difference in hours for top-end and bottom end?

Thanks in advance!

 

[waxhead]

Thank you all!
The 5mm plate compensates for the different distance between pin and top of piston. Nothing to do with stroke.
Still unknown what brand/type of cylinder and cylinder head are used. Cannot find anything on the internet which have the same looks as my head. Maybe one still recognizes it?

I bought a freestyle ski with the goal to backflip it. I know that a stroker engine gives more torque and thus more low-end required for flipping. I think that with this setup you can still flip it, but it will be much much harder.
Unfortunately, this setup is not the 1000CC (with stroker engine) which the previous owner told me.
The price I paid was based on the 1000CC setup. What would be the costs to still transform it to a close to 1000cc engine? I know that 10mm stroke requires a lot of adjusting to make room for the crankshaft. It will even need a stiffening plate at the bottom. But maybe someone can give me an estimation of the costs. Or is it better to stay with 8mm stroker to get the most bang for the buck and get the best performance without huge expenses on maintenance?

Next to this, maintenance. With the standard stroke there is less maintanance compared to a 10mm stroker engine. But how big is the difference? Maybe someone can tell something about difference in hours for top-end and bottom end?

Thanks in advance!

You will also need a new cylinder as the port timing will be all to heck with that extra 10mm of stroke

 

[yamanube]

I would be very curious to see what is going on inside that cylinder. It looks to me they added material somehow for extra transfer port volume....unless it is some kind of aftermarket cylinder.

 

[Big Kahuna]

That is a very old motor . Gonna say it was once a race motor, the pipe dates back to early 90's with the "Mariner Factory Pipe". I think Mariner went out around 92 or so. Back in the early 90's there was a dozen different heads available. It has similar shape to the ADA's but it is not one of theirs unless it is a very very early one.....

 

[WFO Speedracer]

I would be very curious to see what is going on inside that cylinder. It looks to me they added material somehow for extra transfer port volume....unless it is some kind of aftermarket cylinder.

View attachment 440774

It does appear material was added there which would make sense as the transfer port area gets really small with that big of a bore.

 

[BlackMerry]

I received more information and pictures from the previous owner. Did not ask him about the stroker story yet. I need to find out the details of this engine first.
He says that it is a 6mm stroker for sure and with 90.5mm bore the total displacement is 1012cc. This does not match according to the Stroke/bore table.

See the pictures. The top looks like a X64 760 cylinder which is reinforced from the outside. But the bottom of the cylinder looks totally different to me.

Maybe you can easily see what is done here.

 

[WFO Speedracer]

Defiantly a 62t or 64x cylinder, you can tell that by the exhaust bosses on it, 61x cylinders won't go that big anyway

 

[yamanube]

@BlackMerry can you get us a pic of the bottom of the cylinder without the pistons in the way?

 

[BlackMerry]

Unfortunately, I cant. Those pictures are received from the previous owner. He received the pictures by the german guy that assembled this engine.

I only have acces to the engine in the ski at this moment.

Still unsure what kind of head gasket can be used. If i want to check for small end play and piston wear i need the head gasket.

I think that some kind of sleeves are used?

Blowsion. Blowsion Big Bore Cylinder Sleeve - Yamaha 850cc

Blowsion Big Bore Cylinder Sleeve - Yamaha 850cc

www.blowsion.com

 

[WFO Speedracer]

No head gasket it is an o-ring head, you can see it in the pics

 

[waxhead]

Looks like a stock crank to me.
its definitely a 90.5 mm piston in there for a cr500 wossner made it.
THey have been filling on the bake of the transfers a lot for some reason on the out side.

 

[BlackMerry]

No head gasket it is an o-ring head, you can see it in the pics

So the domes also seal by O-ring?
Are those o-rings custom made or is there a supplier where i can order?


Stock stroker for now.
If i want to upgrade in future, what stroker crank can be used with this oem cylinder?
4mm stroke crank is the biggest drop in for 62T cases?
What would be required to get in a 6mm stroker? According to the blowsion big sleeve it can work from stock stroke to 6mil strokers.

Machining of cases, domes and spacer plates is no problem for me. I have acces to milling and turning machines.
Ofcourse I understand that I have to deep into the details about port timing, squish and compression. But i want to know what to expect when going for a 4 vs 5 vs 6 vs 8mm stroke.

 

[Quinc]

So the domes also seal by O-ring?
Are those o-rings custom made or is there a supplier where i can order?


Stock stroker for now.
If i want to upgrade in future, what stroker crank can be used with this oem cylinder?
4mm stroke crank is the biggest drop in for 62T cases?
What would be required to get in a 6mm stroker? According to the blowsion big sleeve it can work from stock stroke to 6mil strokers.

Machining of cases, domes and spacer plates is no problem for me. I have acces to milling and turning machines.
Ofcourse I understand that I have to deep into the details about port timing, squish and compression. But i want to know what to expect when going for a 4 vs 5 vs 6 vs 8mm stroke.

Have you ridden it with the current setup? Try it and you might be surprised. You could also add a laydown exhaust like a pfp and total loss or Zeel and have a significant upgrade in power. While retaining the reliability and ease of maintenance with an oem crank.

Also what pump and impeller does the ski have?

for the o-rings you can measure and find them here:

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

O-rings
ADA 701 Head O-rings:
-Combustion Chamber, viton, -043, pack of 10: 9464K431
-Cord stock for outer seal, 58", buna: 9407K21
-Spark Plug, buna, -020, pack of 100: 9452K74
-Dome to Shell, buna, -024, pack of 100: 9452K78
Protec Cast Rec Head O-rings:
-Style 1*, viton, -043, pack of 10, viton: 5267T57
-Style 2*, viton, -153, pack of 2, viton: 9464K114
Riva 701/760 Head O-rings:
-Combustion Chamber, viton, -153, pack of 2: 9464K114
-Cord stock for shell seal, buna: 9407K21
-Spark Plug, buna, -118, pack of 100: 9452K82
-2nd from top, buna, -031, pack of 100: 9452K118
-3rd from top, buna, -043, pack of 50: 9452K132

 

[waxhead]

So the domes also seal by O-ring?
Are those o-rings custom made or is there a supplier where i can order?


Stock stroker for now.
If i want to upgrade in future, what stroker crank can be used with this oem cylinder?
4mm stroke crank is the biggest drop in for 62T cases?
What would be required to get in a 6mm stroker? According to the blowsion big sleeve it can work from stock stroke to 6mil strokers.

Machining of cases, domes and spacer plates is no problem for me. I have acces to milling and turning machines.
Ofcourse I understand that I have to deep into the details about port timing, squish and compression. But i want to know what to expect when going for a 4 vs 5 vs 6 vs 8mm stroke.

You need to know the port timing before you can simply put in a stroker crank. It changes the timing a huge amount.

 

[jetfreak78]

This head is one of his own production. He let them make in czechia back then, if i remenber correctly.
I dont know exactly, but there is a chance that the head accepts ada o-rings (bigbore)... you have to take it apart and messure...

He did innovativ tunig back then, thinking out of the box (see his transfer port mod on the cylinder) to produce inexpensive power for the people.

I believe the base plate is to compensate the port timing of the 62T or 64X cylinder, so he could port the cylinder to his likings. i'd like to see the sleeves!

His engines riped your arms of if tuned corectly! I´m sure the boat is flippable with this light hull... even without a stroker.

Go ride it and report back...

 

[WFO Speedracer]

I am going to give you a word of advice , I have been at this for a while now ,I have seen a lot of people come and go in this sport , the guys chasing ultimate performance are the first ones to go because their goals are not realistic and if they do obtain it they can't hold on to it for long , put that ski together and go ride it.

 

[BlackMerry]

Also what pump and impeller does the ski have?

The ski has a Magnum 144 pump. The impellor is from Skat Trak, but pitch is unknown.
Thanks for the o-ring explaination!

You need to know the port timing before you can simply put in a stroker crank. It changes the timing a huge amount.

I thought that the cylinder sleeves where made for up to the 6mm stroker crank. I'm not planning to build in a stroker at this time, but maybe in future.... I would like to know my posibilities because I was a little bit misleaded that i bought a 1000CC stroker engine. I wanted to know the price and effort to put in a 4 or 5 mil stroker because the price I paid was based on the stroker engine. Do you think that my bigbore cylinder is suitable for inserting a 4 or 5mil stroker crank with just a spacer below, or machining the domes?
Dont need the details at the moment, I just want to know effort and costs to check if the price i paid was still worth it.

His engines riped your arms of if tuned corectly! I´m sure the boat is flippable with this light hull... even without a stroker

I already have 1 or 2 hours on it. You can find me in the gym a few times a week, and thus I'm pretty athletic and have quite a strong grip, but when you do not control your finger and give a full pump of gas, my grip is not strong enough to withstand the acceleration.

Although, I never drove a standard ski so it is hard to compare.

I have been at this for a while now ,I have seen a lot of people come and go in this sport , the guys chasing ultimate performance are the first ones to go because their goals are not realistic and if they do obtain it they can't hold on to it for long , put that ski together and go ride it.

I fully agree with you. The ski is a lot of fun. Not searching for the ultimate performance. Just interested in the delta in costs between what I thought i bought and what I really got. Beside this the question: Is it still possible with this cylinder to achieve the stroker low-end torque in future? I will contact the previous owner that what he sold is just a lie.


Again really thankfull for all the help and I love the passion that everyone shares here.
Really looking forward into getting more knowledge about the sport and engines.

 

[WFO Speedracer]

Anything is possible but when you stoke an engine it throws all the port timings off , just as putting the CR500 pistons does, as you already have a 5mm spacer plate on the engine it's really hard to say where the port timing would be at, you would probably need to ditch the CR 500 pistons , what you are asking are thing you need to be asking a respected engine builder which most here including me are not. That is the best advice I can give you on that subject, as I always tell everyone, take it to someone who knows what they are doing.

 

[Sparkplug]

"I already have 1 or 2 hours on it. You can find me in the gym a few times a week, and thus I'm pretty athletic and have quite a strong grip, but when you do not control your finger and give a full pump of gas, my grip is not strong enough to withstand the acceleration."

That's the most articulated way to say a ski rips I've ever heard haha

Also, another thread where a bunch of assumptions happened before any logic was applied.

 

[BlackMerry]

Also, another thread where a bunch of assumptions happened before any logic was applied.

That was the point of this whole thread. I bought a ski but was unsure if the information of the seller was correct.
As end result it shows that the tuner has a lot of creativity modifying the X64 cylinder to be able to have a 90.5 bore with enough room for flow.


I do not find a lot of BigBore standard stroke setups on the forum. How should I maintain the machine?
I know that stroker engines increase piston acceleration and speed which causes high maintenance costs.
How about my bigbore standard stroke engine? Can I maintain it like a standard-stroke standard-bore or should I maintain it faster?

Pistons -every 150hours?
Small end -every 75 hours?
Big end -check for play everytime the samll-end is swapped?