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When to rebuild the topend or engine?


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rc46

 
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When to rebuild the topend or engine?

Wed Jun 29, 2005 1:13 pm » Post: #1 » Download Post

hello, can anyone advise, i bought my nsr a few months back, she's only being used for the odd track day at the mo, Andy did the crank around 3000kms (20,000kms on the clock at the time) ago and i have some evidance that Joe Gillings (owner before last) did a ring and piston change at 9500KMs, she now has 23000kms on the clock, asumming they are correct when should i look at changing rings, and or doing a top end rebuild, barrels plated, new pistons, etc etc, is it expensive, who can do it, ? any advise appriciated
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cgallant
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Wed Jun 29, 2005 4:19 pm » Post: #2 » Download Post

Honda's service recommendations are:

20000 kilometers for the top end
30000 kilometers for the crank

If your using the bike for track days, and running it near redline all the time, you will want to do the top end more often then that. I found that in race/track conditions I got about 10-12 weekends out of the top end before it started to feel down on power.

Doing a top end prior to the piston/rings failing is a good idea. Could save you money when it comes to cylinders. Don't wait till the top end fails.

If the cylinders are in good conidtion, you don't need to worry about replating them. That is unless they are out of spec (check the bore against factory spec).

A top end (normal, without heads and cylinders) can be done for about $250.00 (US) if you do the work yourself. While your in there, pull the flapper valves, clean them up good so there is no carbon on them. Also clean all the carbon build up out of the exhaust ports, and the exhaust pipes. This will really improve the power. Adjust the flapper valves when everything is back together.

All this information can be found here in the workshop section. You don't really need any special tools, except for a good torque wrench. Don't go by feel, a torque wrench is the best investment you can make!

Thanks,
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Andy
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Wed Jun 29, 2005 4:27 pm » Post: #3 » Download Post

cgallant wrote:
Don't go by feel, a torque wrench is the best investment you can make!

Come on then Charles... what's wrong with my "torque-wrist"?! Confused
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cgallant
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Wed Jun 29, 2005 4:33 pm » Post: #4 » Download Post

And should we do a leak down test on your bike Wink

Honestly, on my RS, I fight with the reed valve cages, and intake manifolds, and proper torque settings.

just a little off, and they will leak like crazy! I have some good tricks on the base gasket of the cylinder to help prevent leaking, but the metal head gasket I am not sure how to deal with that, excpet proper torque. On the RS I have two O-Rings for the head, so a light smear of assembly grease on those, and it never leaks.

But that stupid intake! Gets me all the time!
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rc46

 
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Wed Jun 29, 2005 5:55 pm » Post: #5 » Download Post

thanks, ive only done one track day and plan only to do 2 or 3 more this year so sounds like winter will be a good time, I dont have the know how to do this, i understand how it works but cheaking limits etc etc i could never trust myself, Ill get Andy to do it, or if mark dent ever replys to emails ill have him do it as he is closer, My rfeind has a RG500 and a Harris frame RG500 tuned to the nuts and he reckons my MC has more mid range than his bikes!!!!! so maybe its okay for now, \ill have a go of his 2 bikes at cadwell on the 29th of July,....... Thanks again,
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