SOLD.
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Polaris UBR 920
- Thread starter Twostroke
- Start date
Spent 5 days trying to get it to run right, would rather ride then constantly be playing with jetting. Going back to a stock 800.
I'll post some pictures of it tomorrow.
I'll post some pictures of it tomorrow.
What are the bore and stroke? I'd like to see pictures too!
If anyone wants photos post your email addrss here.
This will make a good motor for someone, I do not have enough time to tune it. Maybe I needed bigger or bored carbs, I was running stock tm40s.
This will make a good motor for someone, I do not have enough time to tune it. Maybe I needed bigger or bored carbs, I was running stock tm40s.
PM sent for pictures...
Here's what I know about the motor;
I don't know the comp ratio or bore & stroke.
You maybe able to call Fastrax/unionbay and they maybe able to tell you what ratio it is and bore & stroke.
The motor origanaly came out of a Holz chassis raced by Gene Kline. He raced with Rick Ward and Daron Gould. So the motor may of been built origanaly for one of them.
What I do know is that it's a stroker built by unionbay.
Gene raced it 2 or 3 seasons had it rebuilt raced one more season on it then let it sit for several years. Second owner bought it then and used it in a Holz chassis also maybe 200 to 300 miles if that. It allways ran good for him and pulled alot harder then a struther 910 he had.
Next owner ran it one full season [no speedo or odo) then rebuilt the crank last year rode it two or three more times then parted the sled out, thinking he may want to put the more in a newer chassis. He replaced on piston when he did the crank.
Then I bought it.
Photo of when I brought it home, it was a bit dusty from sitting, i've sense cleaned it up some.
I don't know the comp ratio or bore & stroke.
You maybe able to call Fastrax/unionbay and they maybe able to tell you what ratio it is and bore & stroke.
The motor origanaly came out of a Holz chassis raced by Gene Kline. He raced with Rick Ward and Daron Gould. So the motor may of been built origanaly for one of them.
What I do know is that it's a stroker built by unionbay.
Gene raced it 2 or 3 seasons had it rebuilt raced one more season on it then let it sit for several years. Second owner bought it then and used it in a Holz chassis also maybe 200 to 300 miles if that. It allways ran good for him and pulled alot harder then a struther 910 he had.
Next owner ran it one full season [no speedo or odo) then rebuilt the crank last year rode it two or three more times then parted the sled out, thinking he may want to put the more in a newer chassis. He replaced on piston when he did the crank.
Then I bought it.
Photo of when I brought it home, it was a bit dusty from sitting, i've sense cleaned it up some.
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Couldn't keep my hands off this motor. Pulled the pipes, looked inside. Mag side piston didn't look good, pto side looks great. Pulled the head and cylinders and mag side does need to be rebuilt. The PTO side was rebuilt when the crank was so I guess that explains what happened.
I will rebuild this and keep it or sell as is for a discounted price.
Measured the bore and it's 87.90mm. These cylinders are billet with a steel sleeve so no plating to worry about.
Going to call Fasttrax tomorrow to inquire about a piston.
I will rebuild this and keep it or sell as is for a discounted price.
Measured the bore and it's 87.90mm. These cylinders are billet with a steel sleeve so no plating to worry about.
Going to call Fasttrax tomorrow to inquire about a piston.
Not sure if this is good or bad news for those of you interested. I breifly talked to fastrax, they didn't remember gene kline or his motor. The standard ubr 900 has a bore of 90mm, this motor is just shy of 88mm. They built some 700 based strokers and a few custom builds that used seadoo wc pistons.
The stroke length, if it has a forged piston and size of wrist pin will determine what exactly it is. Caged or non caged wrist pin bearings and ID of rod will also be a clue.
I'll post back with what I find.
The stroke length, if it has a forged piston and size of wrist pin will determine what exactly it is. Caged or non caged wrist pin bearings and ID of rod will also be a clue.
I'll post back with what I find.
I got 75mm for the stroke. So 75mm stroke 88mm bore, thats 912cc. Stroke 5mm over stock.
Looking like it may take sea doo pistons. Has caged wrist pins. Will call fastrax again tomorrow to know for sure.
As it sits now $1000 shipped in the lower 48 but if it doesn't go quick I'm going to rebuild it and ask more.
Looking like it may take sea doo pistons. Has caged wrist pins. Will call fastrax again tomorrow to know for sure.
As it sits now $1000 shipped in the lower 48 but if it doesn't go quick I'm going to rebuild it and ask more.
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Here's the scoop on this motor. Talked with Fastrax again then Keith who used to work there.
It's a 950. Only a handful of these made for hillclimb racers.
Stroke = 78mm
Bore = 88mm
Uses Sea Doo 951 pistons.
Keith said he thinks he has some pistons in stock for it but broke his ankle yesterday and won't be able to check for a day or two since he's laid up.
I think I'm going to go ahead and rebuild both cylinders unless someone wants it as is.
It's a 950. Only a handful of these made for hillclimb racers.
Stroke = 78mm
Bore = 88mm
Uses Sea Doo 951 pistons.
Keith said he thinks he has some pistons in stock for it but broke his ankle yesterday and won't be able to check for a day or two since he's laid up.
I think I'm going to go ahead and rebuild both cylinders unless someone wants it as is.
whats the price as is?
$1000 shipped in the lower 48
Feel free to PM me with offers and questions.
Feel free to PM me with offers and questions.
