moly rod question

[jmw76]

Anyone had any experience with these?
http://www.maxspeedingrods-store.com/Suzuki-GSX-R1100-connecting-rods-4-pieces-CR-SUZ-1100.htm

Peter.

[DCRacing]

Nope never heard of them but i am mighty keen to hear about others experience wit them as well, i need a couple of sets in the future,

Keep us updated on your rebuild please.
Thanks

[jmw76]

Anyone had any experience with Precision Performance Motorsport (PPM) rods in Dandenong, Victoria.
From all accounts, their rods have been used in some reasonably high power machinery with not a rod failure recorded.
Now the tag line. PPM's rods are made to their specifications in an overseas factory (quite probably Maxspeeding rods in China).

[jmw76]

I suspect the Chinese rods are probably quite ok. I am just having some difficulty getting confirmation from people who have had real experience rater than rumor.

[jmw76]

Here you go guys.
I posted some of these pics on OSS but thought they might be of interest and spark some suggestions about how I should go about fixing my broken motor.
My desire is to put an oil cooled motor back in as the other options have more issues to solve.

Peter.
192919301931193219331934

[Redmohawk]

What do you want to do mate ? Are you contenplating having a custom set made ? Are you looking for bomb proof or just something better than factory ? How long did the stock rods last before this happened ? What do the other undamaged rods look like ? Have you thought about having them x rayed/magnafluxed/ultrasonicly tested to look for stress points to see if it was just a bad rod or if there all having an issue in the same point ?

From the photos I'm guessing its and oil control problem to the small end ? Possable lock up of rod on pin under compression bending rod near piston skirt ? Then breaking it off on the down stroke . What does the pin look like and piston pin hole ? Any sign of lockup scoring etc ?

[jmw76]

I am currently looking at rebuilding the engine as close as possible to it's current spec. I will be looking towards stronger rods, probably with a bronze bushed small end.
I am no expert in assessing what might have caused the failure but here are my oservations:
- there is some galling to the little end an piston pin (more prominent on the broken bits but also visible on some of the others).
- the galling is discoloration only, the rod and pin surface generally feel smooth
- the pin from the broken rod has a few marks on it, but I suspect these are more as a result of impact with the bkoen rod bits.
- the piston has been damaged by impact with the rod to the extent that the pin boss has pinched the gudeon pin, the ring lands have closed up on the top ring and skirt has been damaged.
- the other pistons/rods generally look ok.
- the other rod/piston assemblies seemed quite free at the little end. There is certainly no signs of binding or scoring. The pins are generally a snug push fit in the pistons when they are cold.

If as you suspect there could have been an oil control issue to the pins, how do I rectify this for the rebuild.

The rods have been in the engine since new, 23 years ago. The last 15 years have been in my little race car.

I am generally advised that the Busa rods are worth considering and haven proven themselves in some very high performance machinery, although they are a bit longer than the std GSXR ones.

I suppose I am just looking for an economical option that will enable me to put the engine back together and for it to run reliably at full noise for another 10 years. Bearing in mind that this will equate to only about 50 - 100 engine hours.

Any advice is greatly appreciated

Cheers

Peter.

[Redmohawk]

I'd go with same stock rods Or Busa rods (if busa are a better option) without breaking the bank Although increasing rod length wont do you any favors on a race motor that lives high in the rev range alot of the time, IE piston will spend more time at TDC for a start doing nothing as the crank turns over , alowing detonation to be a bigger issue and possably needing timing changes to ignition.

Any length increase less than 2% you wont notice on anything less than F1 revs/power , a bushed small end the way to go on 4 stroke stuff .

As for making the rods last a little longer , you can radius the oil holes slightly to increase oil transfer. Think bell mouth on a carb but for the oil hole in your rod, the holes can be matched but don't go much bigger than stock (pick the bigest one and make it consentric with the next size drill then do the rest to match)

Take off any casting marks but don't remove any metal beyond that (balancing at this point picking the lightest one taking the least off , polish the fuckers , then get them bead blasted. It increases the skin density and makes them a little harder/resilient. Take it easy refitting them avoid scratching them when fitting.

[jmw76]

Hi Guys,

After closer inspection, I have found another rod that was about to break. There is a hairline crack right through the little end where it is most heavily loaded. I think it is reasonable to assume that this is how the other rod started to fail.
I would guess that standard GSXR rods are just not up to the punishment that I have been giving them. I doubt that shot peening would have added muchresilience to this mode of failure.

Cheers

Peter.
2096

[Redmohawk]

Hmmm

[jmw76]

Hmmm doesn't provide much to go on. Does Hmmm mean you have no idea at present or that you are just shocked and thinking what the hel has that guy done to that motor to cause that to happen.

There are some thoughts about detonation but the plugs look absolutely fine. It is my experience (with past engines that I have wrecked) that the plugs usually give you early warning of detonation as do the piston crowns.

Peter.
2098

[jmw76]

The piston crown shown was lightly brushed just to remove the fuel deposits for inspection.

[Redmohawk]

Had to phone a friend for consult, What fuel, compression, ignition timing you running was his questions. We both agree piston crown and plug don't show signs of det. End of consult with guru lol.

Whats with the swirl on the valve relief ? Is it possable you have skimed head barrel etc and dropped clearance down to interferance at high rpm/slight valve float ?

Wear mark on edge of piston valve relief is in line with swirl mark also , seems to indicate possable valve contact. Might be enough contact to cause More than just a slightly bent valve stem. Repeated slight contact could cause piston rocking/harmonics reflected in small end as cracking. I'd bet a good look at all your pistons for possable contact points and some crack dye might show issues in the other rods.

And peening will do fuck all for that, better metal(bring on the spending) or heavyer rods (not your friend on the track)

I can dye test your other rods if you want, but I'd bet it will tell you bad things.

More food for thought ! Stock rods with lighter pistons will do the same job as better rods with the pistons your currently running, bonus is less inertia on the bottom end also. Every gram you save on piston weight makes a shit load of difference at 12,000 rpm. Set of slipper pistons might solve your problem.

[jmw76]

Very observant dear Watson.
That piston shown is from the the cylinder where the rod let go (not the one with just the crack).
Unrestrained pistons tend to bump into things they are not supposed to. Flailing around broken conrods, cylinder heads, open valves etc.

Yep, just being funny, sorry.

There was a little valve and head contact during the brief time that the engine kept rotating before it totally locked up and broke the gearbox input shaft.

The other pistons do not have these marks.

No point worrying about the other rods. They are all destined for the rubbish bin.

[Redmohawk]

Ahhh well that blow that shit idea outa the water , honastly thought the dud piston/cyl would have had more damage than that on the top. Troy and I have both seen det (in turbo car I used to have) that didnt show up on piston or plug but hammered a ring land (brought it to our attention) on inspection of the head sign was present at a shoulder between valves.

Looks like your just trying to work the pore sucker to hard for to long. Troy did say stronger conrods will only get you a little further as the crank wont handle much more than the stock rods (reliably) anyhooo . 1052 being a better crank than 1127 he sez 1127 brake 1052 bend then break lol

[jmw76]

I have given the crank a quick inspection with my dial indicator. I thought it might be bent.
Only .03mm runout so she looks all good. Yep 1052 is supposed to be the strongest.
I am trying to avoid using an 1127 crank if I can.

The piston has very little damage considering the pounding it would have had. Totally unusable mind you. The top ring land has closed up, the skirt is bent, the pin eyes have been hammered oval and there is general impact damage top and bottom.

[jmw76]

Plugs are great indicator of possible detonation. I have pulled plugs out of motors before that have had erroded electrodes, cracked insulators and general salt and pepper look. This was when I was younger and less wise. All motors usually died within a short space of time. I have also seen pistons with shattered rings and ring grooves so wide that you could fit a second ring in.

None of these issues are present in my motor. The plugs look brand new and the colour is indicative of a motor runing at it's best.

[Redmohawk]

So whats the plan ? Throw money at this donk or cash up and go to something later with similar/more power and reliability ?

[jmw76]

Well interesting question.

I currently have leads on cases and busa rods from various locations. If I can find a 1052 clutch assembly and gearbox input shaft then I guess rebuilding is a definite possibility.

If not, I may consider installation of a GSXR 1000 engine, ZX10r or ZX12R. These get used quite a bit in similar cars here and overseas. Have a look at these links.
http://en.wikipedia.org/wiki/Formula_1000
http://en.wikipedia.org/wiki/D_Sports_Racing

[DCRacing]

Hi Peter, I have got a spare gearbox input shaft, shoot me you details and i will get it into the post, i am going to convert mine to 6 speed so it is only a spare.

[jmw76]

Thanks DC.

PM sent.

I gather it is a 1052 one?

Cheers

Peter.

[DCRacing]

Hi Peter, It is out of a 1052, i have 2 motors, 1 in a race bike the other is getting modified and will get into a race bike.........eventually.

[jmw76]

Thanks DC.

Did you get my PM?

Peter.

[DCRacing]

yeah got to get my shit together, will get into the shed on sat or sun arvo after work and get it sorted for postage, i will let you know when its in the mail and the cost.
Thansk James

[jmw76]

Thanks James.

[jmw76]

Hey DC,

Any luck with that input shaft?
Drop me a PM with detail or send and email pwstone@optusnet.com.au.

Peter.

[DCRacing]

Sent an email.......