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-   Onroad Nitro Engine Zone (https://www.rctech.net/forum/onroad-nitro-engine-zone-71/)
-   -   OS TR engine thread (https://www.rctech.net/forum/onroad-nitro-engine-zone/40966-os-tr-engine-thread.html)

rcabj 05-18-2005 08:31 PM

Re: Re: Re: Bearing freeplay
 

Originally posted by Darth Vader
Con rod koyak after 1 gallon???
How come...?

I think changing conrod is easier than changing bearing. It's a pain to remove and fit. Have to figue out how to heat up the crank case without damaging the other inner bearing...:rolleyes:

:nod: yeaah...koyak at usual place...a lot of free play its either the conrod bushing or the cranksahft pin :cry: :cry:

...do not use heat to take the inner bearing out...my fren did it and now the bearing also 'koyak'....there is a 'bearing puller' for the job...
---u can use the heat method for taking out bearing if u r sure it is damage..if not stay away from that.

BigDogRacing 05-18-2005 08:50 PM

Re: Re: Bearing freeplay
 

Originally posted by rcabj
i myself just gone through almost a gallon..and already the conrod need to be replace.....as for the bearing i don't see anything...

but if u have doubts u better change the bearing... ;)

detonation is what kills the conrod. If the compressed mixture fires too early then the explosion creates the downforce before the piston reaches TDC thus pushing down on the piston and rod while inertia keeps the piston coming up the bore.

wyl03 05-18-2005 11:15 PM

Re: Re: Re: Re: Bearing freeplay
 

Originally posted by rcabj

...do not use heat to take the inner bearing out...my fren did it and now the bearing also 'koyak'....there is a 'bearing puller' for the job...
---u can use the heat method for taking out bearing if u r sure it is damage..if not stay away from that.

bro .. the best combination is to use BOTH heat + bearing puller.

bearing puller will still introduce stress onto the bearing inner race. but there is less stress required when the crankcase is heated up.

at the end of the day ... i think u shouldn't remove the inner bearing under ANY circumstances unless to replace it. that's what i do anyway :lol:

rcabj 05-19-2005 01:26 AM

Re: Re: Re: conrod
 

Originally posted by BigDogRacing
detonation is what kills the conrod. If the compressed mixture fires too early then the explosion creates the downforce before the piston reaches TDC thus pushing down on the piston and rod while inertia keeps the piston coming up the bore.
so...is there any ways/tips to prevent/control this kind of "detonation" from happening.... :rolleyes: :D

wyl03 05-19-2005 02:04 AM

shims

RayJ 05-19-2005 02:44 AM

Detonation
 
There are several factors that can contribute to detonation.
Head clearance. percentage nitro used, plug, ambient temperature and altitude.

On cool days 50 to 75F almost all engines will perform and put out lots of HP. On those kind of days detonation with stock shimming and 30% nitro usually is not an issue.

On hot days (track temps at 100F or more) detonation may become more of a problem. Head shims will usually fix the problem, but many guys will also drop nitro content to 25% and even 20% and this will also alleviate detonation. If you run lower nitro you will need to lean out the motor more and retune at the track.

Changing to a colder plug will also help with detonation as well.

mrgsr 05-24-2005 12:10 AM

tr r spec fuel economoy
 
hey guys

just wante dto ask if anyone here has the os tr r spec?
my fuel economy is awesome, i mean i can run a 5 min heat and still have just over half a tank left, the engine is still running quite rich with heaps of smoke out the exhaust.

seeing that i have so much fuel to play with, do you think it would be a good idea to bore out the crank shaft for more power ??

thanks
John

yodace 05-28-2005 10:12 PM

Were can I find a company still selling the O.S TR engine for offroad (AD2)?

rcabj 06-02-2005 10:01 PM

os-tr busted...
 
hi....need some advice... after 2-3 litres my tr start havin problem....so i found out the internal bearing already busted....now waiting for a new one...at the same time i check freeplay between the conrod & c/shaft pin...and there is a bit...anyway to be safe i got myself a new c/rod...after puttiing it on the c/shaft the freeplay feels the same like the old c/rod....is the freeplay normal or the c/shaft pin also need replacement..??? just to be sure..thanks...just for info the piston sleeve/compression is still strong...

BundyMan 06-02-2005 10:07 PM

If you have installed a new conrod and there is still "excessive" free play, then chances are the crank pin is worn as well. :nod:

rcabj 06-03-2005 12:28 AM


Originally Posted by BundyMan
If you have installed a new conrod and there is still "excessive" free play, then chances are the crank pin is worn as well. :nod:

thanks mr. bundy....anyway do u or anyone here know the c/shaft pin diameter measurement...just to be 2x sure...thanks.... :blush:

Seisick 06-04-2005 01:55 PM

guys, is there a rear bearing remover tool? I need to remove the rear bearing from my mt12. as for the tr, just got the turbo inner head, and optional hyper head, has the same performance as the r spec or the 5 ports turbo.
but my brand new tz 3 port will arrive tomorrow finally, the piston and sleeve for the tz cost 40 and the conrod 20. its a bargain considering that the rear bearing for the tr at tower costs 60!

nsxshogun 06-04-2005 04:58 PM

HMMMM
 
Well got my tr p T back running. BUTTT I can't go past 75percent throttle. Itll just shut off after about 3/4 throttle. I can't for the life of me figure out whats worng. It is running rich on the top end because alot of fuel is coming out of the pipe. The bottom end seems Ok. I think its either a air leak or somethings up with the 3rd needle.

rcabj 06-05-2005 10:42 PM


Originally Posted by Seisick
guys, is there a rear bearing remover tool? I need to remove the rear bearing from my mt12. as for the tr, just got the turbo inner head, and optional hyper head, has the same performance as the r spec or the 5 ports turbo.
but my brand new tz 3 port will arrive tomorrow finally, the piston and sleeve for the tz cost 40 and the conrod 20. its a bargain considering that the rear bearing for the tr at tower costs 60!

if u mean the inner bearing, yes there is...i have been goin to my fren's if i need to remove those bearing...but i didn't notice the brand or manufacturer...sorry.. :)

rcabj 06-05-2005 10:44 PM


Originally Posted by nsxshogun
Well got my tr p T back running. BUTTT I can't go past 75percent throttle. Itll just shut off after about 3/4 throttle. I can't for the life of me figure out whats worng. It is running rich on the top end because alot of fuel is coming out of the pipe. The bottom end seems Ok. I think its either a air leak or somethings up with the 3rd needle.

jjust make sure your conrod and rear bearing r ok...anything else won't be much of a problem...good luck... :nod:


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