3 year bottom end knocking problem finally fixed, u will be surprised!!

XS650D

XS650D

XS650 Junkie
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Well,i have been posting about this for a few years now but have been putting it of as the knocking finally goes away after a good warm up BUT it has still bothered me.I knew something wes not rite and if I left it alone long enough it would cost me big!. I honestly though it was related to cam chain guide probably fell apart
and was all ready to pull the motor and rip into it.But the engine and bike is running so good I didn't want to touch. Well it finally got the better of me and the knocking was getting louder and lasting longer before quieting down. I decided after some thought to take the bike to a Yamaha guy that has been around these
bikes before and had good knowledge on the inner workings of the motor ect.Well dropped off over day and
first thing out of his mouth is whats with the after market oil filter cooler (Heiden Tuning unit). I explained it was on bike when I purchased. He had concerns about it rite away and proceed to check oil and pressure
and found that the stock filter that comes with the Heiden unit stock was way to restrictive and the cold thick
oil couldent get thru quick enough and something inside the motor (were not sure what) was not getting enough lube quick enough and cried out. Hopefully not crank bearings but possible I guess, maybe the
left side end bearing as the bike would quieting down if on side stand somewhat.Regardless after pulling the filter and tearing off the paper and reinstalling the bike was totally quiet now from a cold start!!
I have since ordered a SS filter ( 35/40 micron) which should allow lots of flow like the Yamaha engineers
designed the engine for. Others may have had good luck with this unit but not on my bike.
Maybe my pumps getting weak if thats possible not sure. But pumped that I finally figured it out and it was a cheap fix. ps: Careful with that Honda filter the unit comes with, very low flow. The higflofiltro unit was
much better that I also tried but still to restrictive, very light knock but much better.Yes we tried a few filters .
Im honestly not sure if this has done some permanent damage to anything and welcome your comments on that. Strangely I did try a 10/60 weight before and it was the same.The filter was the problem all along!
 
There may be some internal wear on bearing ect and if the noise or knocking returns then
I guess it will all have to come apart. Until then I will just ride it. Just a heads up for anyone
contemplating one of these units.Beware!!
 
I am referring to the filter that comes with the Heiden unit that Mikes sells.
Its a Honda style filter .Yellow colour pleats. U can purchase it separate from there site.
 
Well, I'm glad that you got your problem fixed, and that you've come up with a solution that you like. I use a Heiden oil filter/cooler, so your problem is of concern to me, although I've had mine for years, no problems, and what 2M says about our oil pumps is reassuring.
 
Going into the pump is pretty simple and I would be seriously on that track. Repair parts are readily available. Often see really beat up pumps, a torn sump screen allows big crap in for the pump to macerate.
 
TwoManyXS1Bs said:
The OEM trochoid pump, in good condition, is capable of tremendous pressures, and will shove everything thru even a restrictive filter. If your pleated paper filter is restricting oil flow, then should inspect your oil pump...
Click to expand...

Agreed. The key dimensions are:
  1. the DIFFERENCE between the thickness of the rotor and the depth of the rotor chamber (this is called the face clearance) and,
  2. the clearances between the rotor "teeth" and the inside of the chamber.
Measuring the tooth clearances is pretty complex but measuring the face clearance is easy. All you need is an inexpensive digital or manual Vernier caliper/depth gauge (usually around $15-20 at Harbour Fright).

Regarding the face clearance: let's say (for arguments sake) that the rotor was 1/4" thick and the chamber depth was 1/2". The pump wouldn't be able to build any pressure or move any oil - because all of the oil would leak through the huge gap between the face of the rotor and the inside of the chamber.

Now - of course there rotor thickness and chamber depth will be MUCH closer - likely a fraction of a millimeter - BUT - if the clearance is too large, or if either the rotor or the chamber surface is too rough and scratched-up, your pump will still not be able to build sufficient pressure to move the oil through that restrictive filter. The same goes for the rotor teeth - they have to be in good shape too or the thing won't pump.

I don't know what the proper face clearance is - but I'll bet it is less than 0.01 mm (about 0.004"). Perhaps someone has the proper numbers - or you could just toss the pump and get another one.

Pete
 
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2m did some "typical exhaustive exploring" of that.
Here you go; http://www.xs650.com/threads/hp-oil-pump-from-mikes.40991/page-3#post-477090

A chart 2m provided in that thread.
oilpumpspec-jpg.89933

There's also a link to XSjohn (rip) in this thread; Post #4 shows his oilpump side clearance fix.

http://www.xs650.com/threads/a-collection-of-xsjohns-mods.2426/
 
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Thx Guys I guess this will be my next job with the pump.I honestly have not read much in the way
of problems with them BUT....
I think I will just change it out if Mikes sells a replacement unit.My Tach works so
I assumed the pump was working fine. By the way Hugh,s Handbuilt who is a pretty
knowledgeable guy sells his own oil cooler and guess what, runs a screen filter in it as
he states a paper filter is to restrictive for that motor and design.Take it for what its worth!
 
I can't remember any one posting a problem caused due to oil restriction using a MikesXS oil filter/cooler.

Did a comparison on the claims of these side-cover filter/coolers, what i think about how they operate, compared to the claims made.
post #4
http://www.xs650.com/threads/oil-filter-coolers.51898/#post-546542.

xsjohn's, (rip), oil pump mod was designed to give himself more pump pressure/oil delivery, because he installed 2 extra oil feed lines to the 2 rear tappets without starving the head
 
XS650D said:
My Tach works so
I assumed the pump was working fine.
Click to expand...
The snippet of truth in there is a bit inverse. If the tach ISN'T working you better make sure the pump IS still on duty. The tach working only means the shaft is still turning, it is not an indication of pump efficiency. But a pump so bad it doesn't lube the engine is kinda rare.
 
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I will check tolerances on the pump gears ect next. But the fact remains with a different Filter, Mikes Honda filter
replacement for the Heiden Oil cooler vs a Filtrofilter the knocking stopped immediately on a cold start. Im going with a SS unit (on order) no more paper
for me. Time will tell if the knocking returns .But I feel theres probably some wear in the bottom end now having driven
the bike for 10000 miles before figuring it out. Thx for the feedback. Luv this forum.
 
Yes check the pump tolerances and inspect it for scouring.

Not to harp on the filter thing........But..........thinking along your lines, if the filter was the culprit to starving the bottom end then wouldn't that also have caused the top end to starve more. Less pump pressure would mean the oil will travel along the lower galleries easier, making even the small amount of head to raise the oil up into the head area harder, causing oil starvation in the head, cam bearings and make for noisier tappets, especially the back 2.

Went back through your earlier threads relating to the overheating situation. The compression readings were quite concerning when it happened, then 2 weeks later they seem to have stabilized back to a reasonable number and both around the same PSI. That's good, but damage was done.

What the damage was i don't know, but it is often the little end on the con-rod /gudgin pin slap, that can make the symptoms described, Knocking when cold, (thick oil), and then going away when the oil thins and lubes.

If.............mikes Paper filter does restrict, or slow down the oil and the knocking sound has got more pronounced, then opening up the filter screen will certainly mean oil will get to the damaged parts quicker. This is not a solution to the problem..........in fact i would be very concerned and work on a list of theories you have and eliminate them...........Hope for the best but ..........be prepared for the worse
 
Very insightful Skull. Actually my comp readings returned as I got a new tester Lol!!
My Comp Tester decided to crap out but yes the knocking kinda started after letting it over heat.
I guess its inevitable that at some point the motor will need stripped and looked over
but it wont be me,dont feel comfortable going that far even with all the guided help thru the forum.
Its easy to go barking up the wrong tree on this bike. I spent a great deal of time figuring out why my
Speedo was so crazy and after testing with a drill and working properly proceeded to change the cable
and then the speedo drive gear at wheel, ended up it was the speedo internally after finally finding another
unit and testing VOILA!. The tach started to do the same so just changed it out,now all good!!
I cant imagine what fox hole I will do down trying to get the motor sorted out. Time for an expert!!
 

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