# Uh oh , major engine rattle noise:/



## guimond47 (Oct 22, 2009)

Just went for a ride down the feild and on the way back felt like the bike had no top end power. Soo i had to keep it wot felt like it was gonna stall . Anyways put it in the garage and notice this rattling noise on revs . Deff sounds like internal of engine . Let me k ow heres a vid :


----------



## guimond47 (Oct 22, 2009)

30 psi and 50 psi of compression:/


----------



## Waddaman (Oct 3, 2010)

Take your inspection covers off and check your lash (doubt it would be that because it's so loud but it's possible) also see if you can have a look at your valves while your in there. 

What color are your plugs? do they have oil deposits?

It sounds to me like most of the noise is coming up top from valve train, the rattling down below I couldn't tell you. It's hard to diagnose from a video id start with the basics. If it is coming from up top then take your inspection covers off, if you can't see anything from there then take the rocker covers off. If you lost compression it could mean your valves got really tight and your valve overlap is too long.


----------



## CRAZYCRACKAZ71 (Oct 8, 2011)

needs top end rebuild


----------



## CRAZYCRACKAZ71 (Oct 8, 2011)

not enough compression suprised its running​


----------



## guimond47 (Oct 22, 2009)

Yeaa im surprised too. Has nooo power tho at all. It did this after i re adjusted my valves soo like idk . Pistons might of been tired at 8000 km .. And yes my valves are justed propertly and done right with piston at tdc


----------



## Waddaman (Oct 3, 2010)

Yes but did you adjust them on the compression stroke or between intake and exhaust??? If it started doing this right after you did it then it's definitely valves, your not just going to egg a cylinder and loose compression in one ride or break a ring or anything it just won't happen that fast and even if it does it won't happen on both cyls at the same time.


----------



## CRAZYCRACKAZ71 (Oct 8, 2011)

^^100% aggreed. who u did ya valves down stroke or up stroke?


----------



## guimond47 (Oct 22, 2009)

I did my valves and ive been doing it since i got the bike every 3000, and i do all of my buddys valves and ive never had a problem. The bike ran mint after i was done , i was doing donuts in the driveway and catwalks and decided to go wot up and down the field (40 acres long) , and half way on the way back it started losing power ... Sooo :s and valves were done on compression stroke tdc and set on the eye glass to R for rear and F for front


----------



## guimond47 (Oct 22, 2009)

took the heads off and cyl and everything seems. fine. im going to order a weisco rebuild kit at 80mm while im there. just gonna hone cyls. rebuild kit found 1 for 130$ front and rear. soo that preetyy good to me. maybe the rings got weak and dint wnt to hold compression..? but im still wondering what that rattling noise was....


----------



## guimond47 (Oct 22, 2009)

Well i took apart the rear cyl and cleaned it up and re ouled the rings. Got up to 90 psi with the valves fully closing at compression stroke and having the gap set properly for the valves. And only still 30 psi in the front. The valve seats are still mint and not cracked , no bent valve either. Must of been bad luck of the rings weakening and losing compression now . Bike only has 8000 km on it . My dads 09 brute was always more peppy then mine anyday of the week and i have bunch of parts. Will just have to wait and see. Keep u posted!


----------



## NMKawierider (Apr 11, 2009)

Did you find anything on the front cylinder? the one with weak compression? No sign of valves touching the piston...because what it did and when...is what happens when a cam chain jumps.


----------



## CRAZYCRACKAZ71 (Oct 8, 2011)

Check ya valves make sure they arnt worn. May need new valves.


----------



## guimond47 (Oct 22, 2009)

no the valve look great no dings or anything , but as for the noise. its the front cylinder the connecting rod that connects to the crank shaft , the roller baring/ sleeve is shot . theres play up and down side to side about 1/16-1/8 of an inch soooo :/ need a new one of those lawl. and what should the compression be in a brute ? andd my buddys 360 randomly lost compression last year and i slapped new rings in his and he was good to go. he also has 10 000km on the lil 360... LOL he was going deep wen his bike stalled and lost compression.


----------



## NMKawierider (Apr 11, 2009)

Per the manual, using the starter cranking it at 360rpm, the normal usable range for compression is 36-66psi.

Oh, and the Brute uses inserts on the rod bearings like a car engine.


----------



## guimond47 (Oct 22, 2009)

oh okay , well the rear cyl has no play and the front does. thats mostlikly where the knocking is coming from. and i was cranking it using the pull cord. and front 30 and rear 90 psi with oil in both. must be somethin wrong with the front rings and also can i put 750 (85mm) sleeves in the 650(80mm) block. would an machine/ engine shop do that?


----------



## NMKawierider (Apr 11, 2009)

I think you can just put 750 jugs on it even with the 650 heads. But you have other concerns now that she will need a crank..probably.


----------



## 90accord (Aug 22, 2011)

from what i have been told you can put 750 jugs on a 650 and reuse your 650 heads. 


Sent from my iPhone using Tapatalk


----------



## rmax (Nov 21, 2009)

look at my sig ,thats what i did to my 650 cylinders sleved to 85mm with 85mm 11.5 to 1 fst pistons, runniny my 650i heads no problems ,an watch out 750s the 3mm shorter stroke makes it come alive


----------



## guimond47 (Oct 22, 2009)

Well boys i unbolted my connecting rods from the crank and i spun a rod bearing must be from all the cat walk and oil not going up through out the whole motor ..:/ well the crank is fine thats the good news and the conecting rod has wear soo possibly need new rod..:/


----------



## skid (Jun 18, 2009)

when you buy the rod bearings you'll be buying a set of 3 different ones because kawi has 3 different crank sizes and in order to put on the proper bearings you need to use a plasti gage to see which one of the 3 you are going to use. kind of a pain but i know this because i've had to do it more then once.


----------

