STEVE SACHUK

iTrader: (8)

hello and thanks for reding i have a jammin 28 in a jammin x1 and i keep blowing out clutch bearings mostly frnt bearing but has blown rear one . Gear mesh is correct had others look and feel it and end play is fine a little over .5 play a spec i've read in several different tuner books and mags. any other reasons why they would blow out so quickly, running a 5 min qual. and frnt bearing inner race is gone, idd not explode yet but seal is gone and bearing is starting to go. Yes these are new bearings again mesh and end play are correct if not even a little more gap then needed. Im really leaning to 3 things. 1. chassie flex while driving flex pintching out clutch and messing gear mesh. 2. bad set of bearing but all new out of wrapper from protec and reedy bearings black and green seal metal backed 3. tip of crank is slight bent and at idle is hogging out bearing while at idle ...? any suggestions may help have been racing now for 4 or 5 year bashing since "88" but have never run across this issue any help would help thanks

l3asher

iTrader: (2)

Have you tried a new bell??

losiracer78

sounds like you answered you own question my friend the tip of the crank shaft being bent cause the front of the shaft to vibrate which is not good for the bearing and the front bearing is going to vibrate alot more because its closer to the bend

elkman

King Headz makes an extended engine mount for your truck. It will help take the chassis flex out of the picture and may keep the clutch from getting tweaked and eating your bearings. The extended quick change mounts are only about $45.00 or so. Sounds like you are going through that amount of money in bearings pretty quick. My son has a KHZ extended mount in his 8IGHT-Truggy and it seems to do good. I am going to get one for mine soon.
One thing that may be a factor is how you are installing the bearings. Make sure you are pressing them in place by pushing in on the outer ring not by pushing in the very center. It can stress the bearing quite a bit. If the bearing is a really snug fit I will use a socket that is the exact diameter as the outer ring on the bearing and press it in with that, I don't even push in on the center at all.
Kinda like pressing in crankshaft main bearings on a life-sized car engine.
Good luck.

noR

iTrader: (39)

Could it also be a bind in the drive-train? Causing more load on the clutch allowing for more slip, or more heat.

idk, I had alot of bearing problems myself a while back. They seem to have calmed down a bit though.

Paperman 90

iTrader: (43)

hey i had crt 1 that was doing the same thing i to had to put a z brace on mine and that help

PTP Racing

iTrader: (2)

I know a guy who had the same problem with those engines. We theorized it had something to do with the crank balancing. If yours is bent at all that is more than likely the cause of your problem.

STEVE SACHUK

iTrader: (8)

thanks for all the tips ill try it i have a different motor going to try that vspec again

j_blaze14

iTrader: (34)

chassis flex

losi_racer

iTrader: (25)

its not chassis flex. in my 8t and now 8t 2.0 and also in both my dads truggys, We never ran the extended motor mount and never blew bearings like that. If i wanted to(he does) i could just replace bearings when i replace the clutch, we use avid bearings.

i did have an problem like you are in my buggy tho, every race was a chance to blow my pads from bearing failure. Ended up being my front bearing of my engine leaking a slight which was causing my bearings to go.