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Coyote
12th December 2004, 17:22
I want to know if the 1992 CBR250RR (MC22) have interference engines or not. Also, does it have a cam belt or cam chain?

k14
12th December 2004, 18:29
I want to know if the 1992 CBR250RR (MC22) have interference engines or not. Also, does it have a cam belt or cam chain?

Wtf is an interference engine??

The answer to question 2 is neither, gears all the way :Punk:

toads
12th December 2004, 18:39
as far as i'm aware they have neither a chain or a belt they are gear driven cam's

onearmedbandit
12th December 2004, 19:52
http://www.cr-x.org/cbr250/forum/

TwoSeven
12th December 2004, 21:22
They are gear driven cams (and the best i've seen - take a hammering) and no - not interference engine as far as I know, although the tolerence is pretty close. You'd have to skim the head and remove the gasket to get a valve and piston to meet I think.

I've not measured the gap between the piston crown and the valve at full extension. so I could be wrong.

(from memory an interference engine is where the valve comes down lower than the top of the piston crown at TDC - if the timing is out, the two will connect and 'interfere' I suppose).

Coyote
13th December 2004, 09:48
Wtf is an interference engine??

A poorly designed engine. If the cam-belt/chain breaks, the valves stop and the piston crashes into them, destroying the piston, the casing, rendering the engine useless. Most modern cages have interference engines and thats why you have to replace the cam-belt/chain so regulary cause when it happens in a cage, you have to remove the engine, and replace it, and in most cages, it isn't worth it.

I'm pretty damn relieved the CBR runs on gears

Note: this is what I've been told, if it is wrong, correct me

vifferman
13th December 2004, 09:55
A poorly designed engine. If the cam-belt/chain breaks, the valves stop and the piston crashes into them, destroying the piston, the casing, rendering the engine useless. Most modern cages have interference engines and thats why you have to replace the cam-belt/chain so regulary cause when it happens in a cage, you have to remove the engine, and replace it, and in most cages, it isn't worth it.

Note: this is what I've been told, if it is wrong, correct meAlmost right. It's not 'poor design' as you say, and although it can potentially result in major engine damage if a cambelt breaks, it doesn't always. Sometimes nothing happens, and sometimes it's limited to valve damage (as on my FahrtSturm when the previous owner had the CCT break and the camchain skip some teeth on the camgear. Oops.) And regular replacement of camchains isn't usually required - they usually last a long time (except on Hondas....)

Sniper
13th December 2004, 10:05
Bro, nothing wrong with the CBR (Someone will disagree)

Just to reinforce what the others say, even though you know, the cams are gear driven and no, it is not an interference engine. Just out of curiousity,why do you ask?

Coyote
14th December 2004, 08:50
Just out of curiousity,why do you ask?
Out of curiosity and paranoia :eek: