strokers and rods

[THEMOTORHEAD]

which length rods are you using with what results?

longer is better but with tts runnin very low rod ratios is anyone having any problems?

[dragzooks@indy]

i spoke to richard and he is running a really long rod in the 1900cc
contrary to what people on some boards have been saying, that engine uses the +10.5mm crank
not a 19mm like i have read

he said he has added enough length to the rod to get the rod ratio back to stock which is around 1.89 : 1

when i built a stroker 5mm we werent sure about getting the cam chain to have enough slack and getting the motor mounts in the head to line up with the frame if we used regular length carillos and a spacer plate so we used .100" shorter carillos (neither did we have the time to have special stroker pistons made to solve the height difference that way)

it lasted well enough in my opinion for a race bike that got beat up on the street
bout 2000 miles and bunches of passes and dyno pulls

it finally started eating up the rod bearings
upon disassembly i found the pistons were "kissing" the head just a little
squeezed it a hair too tight p/h wise and he banged it off the rev limiter repeatedly
i think it would have lived alot longer if not still be alive if not for those two things
banging up against the head definitely pounds the shit out of rod bearings
 
richard claims his 1900 looks great after disassembly and we are in the process of trying one of those out with longer ti rods to get the rod ratio back to stock and reduce the reciprocating weight/load on the bearings

everyone argues that the oiling is not the problem and its things like the compression being too high or the babbit being too soft and the oil film shearing it,... but i just cant make sense of how the exact same bearing lives in an oil cooled in more extreme situations (high comp and NOS shootout levels)
compare an oil cooled and busa oil pump and you'll see a big difference
also the oil cooled rod ratio stock is 1.98
more favorable for less bearing load/cylinder thrust loading
????????????????????

[dragzooks@indy]

above is refernece to tts' personal 1900cc engine
i dont know what he is selling in kit form or what rods people are using that just buy the crank alone

and i know some people are gonna plug 73.5mm stroke into b*b*s*.7854*4 and wonder how in the hell is he getting 1900cc

reverse out the math and solve for the b (bore)
and then wonder how the hell you get that much offset  

[AssAbuser]

How on earth could you expect someone to answer all of those questions....

Well here goes

yes
no
no
yes
maybe

hope this helps

LOL  

[dragzooks@indy]

nick,
lmao

[Gixx1300R]

My 5mm stoker has over 4000 miles with numerous dyno pulls and I ride it daily. I used stock length Carrillo Rods with custom Zero deck height pistons. I solved the problem of the cam chain being too tight by making a spacer plate for the cam chain tensioner. You can always by a longer Cam chain or use a Manual tensioner. When I built the motor A.P.E didnt offer longer Cam chains. I didnt want to use a Manual Tensioner so I went this route. I also went 2 sizes larger on the Crank bearings.
 

[Kamikazek9]

when you stroked the crank, which route did you go---Billet crank or re worked stock? And which company would you suggest between Falicon and APE?  

[cstraubs1]

Gixx1300...where did you get your tensioner spacer???

thanks bobby

[Gixx1300R]

I CNC machined it myself. I made some extra ones and sold a couple to some board members awhile back. It is a must if you use the A.P.E space plate under the block and use a stock chain tensioner (something A.P.E should provide with their spacer plate). I sent my stock crank to A.P.E. Falicon is a 45 minute drive for me and I will never use them or any of their products again.

[Landspeed Larry]

Got a 85x73.5 motor with the TTS crank and rods. It makes almost 150 ft.lbs of torque so I gear it like a turbo to keep the piston speed reasonable. Don't like the short rod but it is the easiest solution so I just drain the oil often and look for flakes. The more radical the engine, the more maintenance, and the shorter the life. There is no free lunch.

[bigabusa]

My reasons for bearing wear. one a lot of the drag guys don't give the bearings any running in, plain bearings need bedding in, run them in like Suzuki say and the bearings survive much longer. (2 hours on the dyno light load 1/2 revs would help). The other thing is that my cranks are Nitrided and very hard, std OE cranks are soft so no matter how good the finish is the bearings take longer to bed in. I have talked with bearing manufacturers and they all think that running a small bearing clearance helps keep the oil film between the bearing and the journal and that clearance should be between 7 10ths and 1 thou. I can get a ptfe coating on the shells up to 6 10ths thick if you have problems getting this. I have also source a much better shell for the 8.5mm cranks (40mm journal). Another improvement is to get more oil up to the bearing. I now do a 30% bigger oil pump (you can view it on my web site www.tts-performance.com under hayabusa engine parts. Saval Racing will supply you one in the US. I have been told that the rod length (my rods are now 2mm longer)is not an issue on bearing wear but it is obviously on piston thrust. I live in F1 country (Cosworth are only 10miles from me). F1 engines run as compact an engine as possible this means short stroke and short rods. they run for a 2 hour race up to 18,000 rpm. I hope this will help you guys keep these engines together longer. Also don't forget to keep the oil level well up. I run 4.5 litres.
By the way I have only ever had one of my motors run a bearing and that was my stupid fault for running the oil at the bottom of the window. I ran a 1664cc motor on flying Kilo's, did 21 runs (flat for 2 miles) over two days and the bearings came out fine and that was with 120 bhp of gas on top.

[THEMOTORHEAD]

richad i need 4 oil pumps asap
whats the hold up on these
havent heard anything from saval as to delivery time
and break in time to work harden bearings is everything to survival of the bearings

[bigabusa]

The pumps have left UK so should be with you any day. Thanks for backing me up on bedding in bearings.

[pooh]

quote:Originally posted by bigabusa:
I ran a 1664cc motor on flying Kilo's, did 21 runs (flat for 2 miles) over two days and the bearings came out fine and that was with 120 bhp of gas on top.

You obvioulsy put that one together with a lot more care then you did with mine.          

[bigabusa]

Pooh by name Pooh by nature, talk to me directly if you have a problem. It could be the fault lies with you?

[pooh]

..........edited for the time being.........

[AssAbuser]

So what you guys are saying is that you can put a coating on the bearings or the crank to make them last longer without failure????

Also from what I am noticing is that compression seems to be the major bearing killer no matter what you do...So the question I have is that a 1430 with 13-1to 13.5-1 should be easy on bearings correct...

also where can I get these bearings coated and how long is the turn around time???

[THEMOTORHEAD]

compression kill bearings
look at it this way
its force of compression vs. film strength of the oil
at some point the compression at low speeds pounds the shit out of the bearings
while low compression just keeps rollin
so try pumpin up the oil pressure use good 15 50 oil and it will significantly lower the risk

[AssAbuser]

That is what I have come to figure out....I am going to drop my compression and change my bore size that might help aswell....

I already run the 15-50 oil and have the gear and the windage tray and run 4 quarts of oil but still got problems and I am figureing out that it is the compression banging the shit out of the bearings and causing the undepndability so that is going to change...

[dakinebusa]

Nobody seems to be concerned about how much crush the bearings are getting in these motors.

According to Smokey, insufficient bearing crush is the #1 cause of pounded bearings in motors  that are otherwise right.

It could be that manufacturing tolerance stack up is causing some bearings to have insufficient crush.

Anybody ever measure it before assembly?

Suzuki doesn't mention a beaqring crush spec anywhere I know of.

In a small block about .003 to .005 crush works well with a clearance of .0015 to .0025.

?????????????????

[Johnnycheese]

crush?

[Steve A]

Where the ends of the bearing shells meet - infinitesimally- prior to the rod cap meeting the rod.  By doing this , it keeps the back of the shells very tight against the rod and cap and keeps the bearing from being hammered as much.

[Johnnycheese]

Thanks I just didn't know it had a name

[Steve A]

Part of the theory is that it prevents an oil buildup between the bearing shell and rod or cap.  With the oil buildup it allows the bearing shell to flex as the crank rotates and eventually flake off the bearing material from the backing (shell).

[dakinebusa]

Smokey sez this....

Take an old bearing shell, put it on a steel block and hit it at bdc with a ball pein hammer.  What happens is the ends of the shell draw in.

When a motor detonates it is like a hammer blow.  The bearing shells flex and the ends pull in.  This scrapes the oil film off the crank journal and you get a spun bearing.

More crush reduces this tendency.  Doesn't eliminate the problem but it helps.  Pinning the inserts helps some too but NOTHING will make a motor live if you get significant detonation.

I would like to know what kind of fuel and how much advance the big motor guys are running when things go bad?

All this doesn't explain why #2 seems to be the one that goes.  My guess is it is either an oiling problem or some kind of vibratory resonance in the case or crank.

Be interestingto see if the new hi volume pumps help.