Spidermax RS loosing oil filter disaster

Sunday afternoon, after a nice ride through some local hills, on the way home disaster strikes...

When the oil and filter was changed in the shop before the bike changed owners 3 months ago, the person who did the changing installed the wrong oil filter.

Instead a HIFLO HF184 a smaller HIFLO HF147 was used.
The HF147 is used for a Yamaha 500cc TMAX and the 500cc Kymco Exciting.
The difference between the 147 and 184 is not only in diameter and highs but also the thread diameter is is a bit larger on the 147.
HF147 and the original Piaggio filter for the 500cc scooters (the HF184 has the same dimensions)

the HF147 has an inside diameter from 18.5mm

the HF 184 / Piaggio 878068 has an inside diameter from 18.0mm
You can screw the HF147 on to the Spidermax (Piaggio MASTER engine  400 and 500cc) without problem and even can hand tie it so that it seals.
If you use a tool to fasten the oil filter, the thread will skip and the oil filter will come loose and you will not be able to re tighten the filter again.

Back to our young, bright eyed and bushy tailed couple what enjoys the first trip with the newly bought Spidermax. Because weather and other condition there is just a bit over 300 km on it since it left the shop less than 3 months ago.

5 kilometers away from home - the HF147 oil filter has had enough from the vibrations and decides to loosen up a bit. - Oil begins to seep out of the filter and makes a dotted line on the street while the riders in blissful ignorance enjoy the slow ride through the back roads of Valencia.

4.7 km from home - the filter enjoys his new freedom, decides to see a bit more from the road and loosens up some more. The center stand is in the way of total progress and keeps the HF 147 from falling onto the street. The oil enjoys its new freedom too and happily coats the rear wheel and sprays the street.

4.5 km from home I wonder why the Spidermax sounds a bit more clackery than normal.  - Is it the road surface or the maybe the new open face helmet?

3.9 km from home my dear wife asks me, what about that red light on the dash board, one view reveals the red light is the oil pressure warning light and and an instant later I bring the Spidermax to a stand still and the engine dies even before I can turn of the ignition. Looking down I see oil running on the street.

nearly lost HF147 oil filter, the only thing what keeps the filter form falling onto the street is the center stand

this is how it should look like - the smaller filter was nearly invisible since it was shorter

I think to myself, never in over 40 years with vehicles did an oil filter come loose - what a crap.
Well it is Sunday afternoon, out in the country where streets seldom have names. Until some help arrives and finds us there will be some time. So lets have a nice walk home.

At home put some oil, oil filter wrench, paper towels in the car and head back to the poor Spidermax.
Will she even start after loosing all her oil?
Tighten the nearly lost HF 147 back into place hand tight I use the wrench to really tighten the filter. There is little to grip when hand tighten the filter since the filter is surrounded by a non removable cover.
For some reason now the filter slips through and and will not tighten anymore - not even hand tight.

I drive back home again ( it is so much faster than to walk...) and get the Piaggio oil filter out of my old Spidermax. This is when I notice that there is a difference in filter size and start getting the caliper out to measure the thread diameter.
As mentioned above there is an explanation why the HF 147 was holding, why it had to come loose sooner than later and why when really tighten the filter the thread would slip.

So with my old Piaggio 878068 filter and some hope we are in the road again to the stranded Spidermax.
I needed the maximum amount of oil (1.75 liter) to fill her up again what showed me that all oil was spilled. Sigh!
Pressing the starter did not much but after good 30 seconds of cranking the starter the engine started and sounded normal.
Driving carefully and with low rpm home there was some expected hot oil smell when I turned her off.
Testing the next day, the engine worked normal but when turning the engine off there was the hot oil smell again and also for over 2 minutes there was some light smoke coming from the exhaust area opposite to the filter.

A repeated test ride had the same outcome.
I wiped down all the spilled oil I could find and will test it some more.
This time there was no smell and no smoke, but then the bike was not as hot as it was the 2 tests before.

So for now I do not know how much the engine was damaged.
I keep you posted.

After 2 more test runs the oil smell and smoke is gone now, but there is definitely something wrong with the water cooling system. It looks like the second cooling circuit engages sometimes after the fan already engaged and then the temperature spikes in a short time to max levels. This happens only when driving very slow.


  1. Heloo,i,m a new owner of spidermax gt500.When i turn the key o get the low oil presure warning, but it goes away after about 10 seconds or if i start the bike.To me it rides normal and i think it sounds normal too.Do you know what it could be?And thank you for all the info and hard work here, it's amazing.

    1. You probably know it by now. "Oil preasure low" warning after turning your key is totally fine and normal all spidermax has it. I have been seeing it every time i start the engine for last couple of years. I gues its just the computer running some oil preasure test. So don't worry. Just wait for it to go away and you're ready for take of. Have a good one ;)

    2. User manual:
      "The digital instrument board features a control system displaying a "LOW OIL PRESSURE" message (B - § 3.11.6). The message appears when the vehicle is turned on to signal that the check function is working. The message disappears automatically after a few seconds. It will only reappear during vehicle use if there is actually a low oil pressure problem"


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