'99 400F questions

5 replies to this topic
  • Jason

Posted November 28, 2000 - 10:11 PM


I've had my bike for a few weeks now, and I love the thing, but I have a few questions.

1) I've fouled two plugs so far. I usually have little trouble starting, but these times in particular, I kicked till I was blue in the face and it never caught. About two out of three kicks, it would sputter for a second and die. Both times I put in a new plug, and it started first kick. I'm 99% positive that jetting is stock, I'm at sea level, it seems to run great. Could my plug fouling be a result of running rich nonetheless?

2) I read up on what everyone had to say about changing oils, and I just don't see the importance of cleaning the oil strainer every time, like was suggested. I was expecting a very fine, special filter and what I found after wrestling with hoses and skid plates for half an hour was a heavy screen wire coarse brand new looking screen. I just don't see how this thing could catch anything, or ever become contaminated.

3) How long does it take for the glitter in the oil changes to go away? I'm expecting my bike has 20-30 hours on it, and I was alarmed to find my used oil pretty glittery.


  • Boit

Posted November 29, 2000 - 02:21 AM


Jason: It appears to me that this particular screen is coarse due to its design as a first-line defense of larger debris in the oil. Since it is located at the exit of the frame oil tank, it catches pieces of gasket material, welding slag, paint chips...etc. before these particles can get further along and possibly get caught in the oil pump. Smaller particles pass through and get trapped in the fine micron oil filter. I only found the coarse screen to have a few particles trapped when the bike was only a few hours old. I checked it again after about another 30 hours of engine time with no debris at all. My oil only showed signs of metal glitter after I installed a Hinson basket. I panicked! I pulled the basket back off and looked for signs of rubbing on the inside of the case. I could detect nothing. Maybe I didn't clean the driven gear and backing plate good enough after grinding off the heads of the rivets. Grinding magnetizes metal a little and those shavings may have stuck without me noticing. I'm disappointed in myself for not being more thorough. Oh well, I'm far from perfect. In any event, after two oil and filter changes, there's hardly any metal particles showing up in the oil. Hopefully, damage was/is minimal. I won't make the mistake of accepting "good enough" again when it comes to doing work on my bike. I will allow my perfectionist nature prevail from now on.

  • Kennymac

Posted November 29, 2000 - 07:05 AM



When first starting my '99 400 after transport I have the same problem. Kick and kick and then it will finally start. I found that if you "clear it out" first then starting is not much of a problem. What I do:
Open hot start valve.
Hold open decompression lever.
Kick 30-40 times (really! it may take more).
Try to start normally - choke etc...

I think what happens, in my case, is the the engine gets flooded after bouncing around the back of my truck. If it is cold and NOT transported I have no problem starting at all. That's how I came to this conclusion. Hope this helps!!


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  • Hick

Posted November 29, 2000 - 07:14 AM



The oil strainer only needs to be cleaned when new to catch the paint chips etc. that Boit mentions. If you continue to find aluminum particles (“glitter”) in your oil I would say that a little investigation is in order. The only time I’ve found stuff like that it was due to case damage. I suppose the glitter COULD be clutch material, either way if it’s in the oil you should be finding it on the filter as well. You really should change your oil every few rides (but you can clean and reuse the filters).

The plug fouling is probably just a 4 stroke learning curve thing, I fouled a few plugs myself when I first got my 426. When you start it turn off the choke as soon as you can (turning up the idle when cold helps keep it running) and stay off the throttle completely until the bike is warmed up a bit (one or two minutes should be plenty).

Hope this helps!

  • Boit

Posted November 29, 2000 - 10:00 PM


These metal particles only showed after I had installed the new Hinson basket. I'm changing the oil tomorrow and will pay close attention to this. I've also installed a Scott's permanent type oil filter. At every change, I remove this filter and inspect it to see what's being caught, then I shoot carb cleaner into the inside to knock off any particles clinging to the screen. This oil filter is claimed to be of a finer mesh micron screen than stock. I'm crossing my finger in hopes that the metal particles will have cleared up....or at least, decreased substantially.

  • Boit

Posted November 30, 2000 - 01:02 PM


I was lucky. Just a little metal shavings in the oil...caught in the oil filter. I KNOW how everyone was losing sleep over this.

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