Bad fit, Hypertek tank?

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Well-Known Member
Apr 21, 2011
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I recently bought a 54mm hypertek motor with a 835cc tank.
I tried to test fit it in a PML 54mm tube.
I found that the forward end of the tank where it starts to round out does not fit in the tube.
I turned the tank around and found that most of the tank fits fine.
It seems to be only about the last 1"
Anyone else run across this and if so what did you do about it?
I have an 835cc Hypertek tank and it fits just fine in a PML 54mm tube. I'm wondering if you have a faulty tank. I've never heard of your problem before. If you have a set of calipers, I'd measure the tank at the nozzle end and then measure it near the curved top end. If there is much difference, and it sounds like there is, then I would contact Hypertek about a replacement.
When the 54mm 835cc tanks first came out they had that "bulbous" problem on the end. Oscar Valent of Star Rocketry, sanded the end of mine per Anthony Cessaroni's just fine after that. If I had it to do over, I would have waited for another one to come the mfg for a replacement.
Thank you for your replies.
I did email the manufacturer late last night and was pleasantly surprised to get a response early this morning from Anthony Cesaroni himself.
The tank will be replaced.