Group Buy - Honda 400cc +1mm pistons -

[racesupplies]

I think they should be light,i sort of started this.I used them a while ago for 350K4 pistons.They are either machined from forged slugs,or 3d machined from forged bar.I know what you mean about JL,i have seen them fail in vintage race cars. The ones I saw were castings,they stress releived themselves and pinched the wrist pin.

[g-force performance]

Again, I'm curious - does this pricing include rings? You said so, but are you sure? What are the rings? Are they making custom rings, or using something off the shelf. I ask because with all the crazy custom expensive stuff we've done, we've never been able to afford custom rings. We always had to make the piston fit some ring from another bike. --Thanks.

Lohmeyer - 55,56 & 57mm rings are more available. We couldn't find any decent 58mm rings. The old JE 444 kit used GPZ550 Kawasaki rings that were just so thick it didn't make sense.

You guys might want to ask Omega what the ring thickness is. The Yamaha OE Rings for the FZR400 (they're available from 56.00mm to 57.00mm in 0.25mm steps) are 0.8mm thick. They are about the best rings you can get for that size. If you're going to stick with 55.00mm bore size, stay with the Honda rings if you can.

I am curious to hear how these go. I am so tempted to get a set myself for testing against our uber-expnsive unobtanium jewelry.

Mike Norman
G-Force Engine Development

[g-force performance]

8: Do you have a picture from one of the previous sets that have been produced? I think a visual idea of what we will get will help any people who are undecided at present.

If they can send you an IGES (.igs) CAD file I can load it and post JPEG (.jpg) images to this thread. I can also get a weight estimate from that CAD file if they don't provide one.

Mike Norman
G-Force Engine Development

[racesupplies]

I spoke to Omega this afternoon,they can get 55-57 rings,but i dont know where from.I couldnt see why the Cosworth kits you had were so expensive,was it a small one off batch? Omega have combined with accralite now,they were both top piston/top end part makers,their products have never been as expensive as cosworth.I cant recall anyone having problems with them.Certainly not in the JL bracket.Perhaps we will see.

[racesupplies]

Sorry Mike,I typed JL,they are my enginering suppliers.I meant JE,neither make good pistons.

[CMSMJ1]

Thanks Mike for your input - I'll ask the questions of them and see what we get.

[ScottieDucati]

Which bike are you referring to, the CBR400 or the NC-30/35?

I'm trying to decide what bore to do, I don't have racing regs and figure the largest bore I can safely accomplish would be best. It's a trackday bike after all, but I'm no lightweight and could use the power if I can get it!

[racesupplies]

They go in either.

[ScottieDucati]

Great talking to you Mike and thanks for chiming in!!! Looks like I'm going with 57mm (+2) pistons and well, I'm pretty excited. Probably going to end up with a bike that will surely become my favorite of all time :D

[racesupplies]

I keep saying I am going to keep quiet,but I have my specs sorted with them,whatever the price.I just wanted some higher top forged slippers.I know nothing about V4s,just pased the contact on to you lot.Really enjoying the forum,wish I had joined years ago.All the best with the orders,must go and get my bike together.Cheers Carl.