All I can think of is the C clips are not properly seated, or they are getting damaged some how when you are installing them. Is the little tab piece breaking off and leaving the rest of the clip seated in the piston, or is the whole clip coming out ? I use a jewellers magnifiing eyepiece to check the clips are properly seated when I change them (yeah I know I'm getting old and going blind ). But it can be hard to see if they are locked into the groove properly. Just a tip I was given - install the clips with the gap facing vertically, not horizontal. At high revs the clips can contract and on the odd occasion contract enough to pop out of the groove. If they gap is vertical when installed it helps to keep them in (apparently so, according to a 2 stroke motorbike racing friend). Something to consider.
It's not a common problem as far as I know.


Easy solution - Replace the shonky O rings with fuel tubing (see my post some pages back, or PM me for details). Or get a set of Nitrile O rings from Massive Mods in Australia.
Take out the long LSN (which is what will be causing your tuning problems - hence blown plugs - too lean on top) and shorten it from 1.6" down to 1.42" with a rounded end. Fit it back in and your GO will tune like any other motor out there.
I run the fuel tubing O rings and shorter needle in both my GO's and have no problems what so ever. Awesome performance, 12 min + run times, super reliability.

It didn't break the pin. The clip that holds the pin in broke and locked up the piston. Twice now with new P/S/R's.

Hi Adrian, Pity about the weather last weekend. I was looking forward to seeing your new Gen 5.5 7 Port go hard
Never mind, next meeting we should have the 2072's bolted on
I am keen to see how these pipes will perform. Everyone so far has been very pleased with the performance. My only concern is that the larger volume chamber will not fit into the X Ray without melting the tank or the body. It's a pretty tight fit in there with the slightly angled engine mounting on the Ray.
See you at the Tron in July

I noticed when I did mine it did not want to fit in or seat all the way. that's what it looked like. I took a small screw driver and spun mine around in the hole to make sure it was set all the way in. and it did pop in further. just a suggestion.

thats a good idea Matt the clips are so dam small and the groove to we all need a huge pair magnifing glass to see it properly ,as grizz said

I did look at it like I do all of them I put in but it looked like it was in to me. I'll make sure I check the next one if I decide to drop another 100.00 at this thing.

sorry man, I miss read your post, like grizz and big matt have posted I always check the clip even on a new P/S/R set as nobodies perfect even a factory.

yeh the weather over here sux at the moment. I dont think there should be too much of an issue with the 2072 fitting in the 808 as I'm thinking it will be similar in size to the 2047 but maybe 1 of the aussie boys who have 1 could shed some light on the subject.

But what are the chances of getting 2 in a row that did the same exact thing from 2 different suppliers?

The way I install the clips and wrist pin are as follows. I install one c clip in the piston first,then install rod and con-rod. then I push on the wrist pin with a phillips screw driver to make sure the pin would not go through the other side. That tells me the c-clip is seated into the groove. do the same for other c-clip take magnifier to make sure all of the c-clip is seated in the slot.

All i could put it down to is really really bad luck but like i said earlier there maybe some underlying problem thats you've missed we all do it when your looking at something and your frustrated because you can't figure it out ...you miss a little thing that can make all the difference.


hell I missed the word "clip" in your first post

maybe send it off to someone like 22 racer to look at it you just never know

Adrian

Well I'll be sure to double check next time. I've never had a clip break in any of my other motors before and it's just kinda crazy I get 2 that blow with less than 2 gallons combined. I would think if the clip wasn't in all the way, it would of came out during break in with all the extra fuel going in and all. I pulled the pin just to look at it and both ends are severely worn. That's something I've never seen yet either. You'd think this thing had 10 gallons on it.

Ya I know what you mean. I am going to get in touch with Mark at Massive or 22racer and see what they think. I just started break in on my 7 port. If it does the same thing I'm going to shit kittens.

I know how you feel I used to run Nova's until they changed to 14.5mm rear bearings and i had 2 plus-5t's drop rear bearings at under2 gallons and the cost of a rear bearing alone was almost as much as a P/S/R set for a go when the 2nd engine went it took the P/S/r with it now it's a very expensive bookend

good luck I hope you get it sorted

Thanks, so do I. Do all the Nova's have that issue? I Got a P5XS too and wonder if I should look at it before counting on it as a back up.