My temp gague go to 99c and then hot after 7 or 8 laps. Stock rad no fan. I have added maybe 8 oz's of water wetter in 6 track days. It is never boiling when you remove the cap but the overflow bottle is full at the end of the day. It dyno 70 hp at Marietta Motor Sports and the guy who wants to buy it said Speed Works said it should have 78 or so hp and the head might be leaking water. The oil has never had water in it. I bought the bike from Mark Hurt who bought it from Jeb Plamer (sp). Thanks, PR PS You guys and ladies crack me up and I meet Tom at TGP and he is fast (1.04) and his lady looks good.
I had a blown head gasket once. The symptoms were similar, altough it was more like 8 cups of water in 1 track day.
I have a 88 FZR400 with similiar symptoms. I believe the head gaskets, etc are good. The "bad" thing is it seemed to get a little worse every weekend.... It actually boiled over during a couple of Solo 20s. (Water and wetter only, don't worry...) The motor will be getting tore down here real soon and I plan to have the cylinder head magna-fluxed to check for cracks... No water in oil, but some could be getting in the cylinders, I guess (???) If I discover anything interesting, I'll pass it along to ya.
I do believe that Sid Thompson's 400 boiled over alot. The fix he ended up doing was mounting a FZR or YZF 600 radiator in to the bike. I think it mounted right up with little to no mods or fabrication. I can contact him if you like or send him this thread.
You are correct, Sidman's bike overheated a few times late in the season and had to mount a bigger radiator. After that he had no more overheating. Once the parameters of the stock engine configuration has been passed and higher compression is added- the stock cooling system is quite overtaxed. I had to do the same thing on my EX. Sid is the man on 400s.
Yeah I had the same problem with my stock 400 motor overheating. I put in a F3 radiator and had no more problems. It dropped the temp by ~ 10 deg while on the track. Don
OK, here's what I found from experience with my son's '89 FZR 400.... Not trying to sound "demeaning" re: anyone's mechanical expertise, just trying to help save some money. 1. Experienced overheating about 5 years ago. 2. Everyone advised that it is a well known problem that the FZR 400 is subject to overheating and the obvious solution is an FZR 600 Radiator (around $500). 3. If the oil doesn't look like a chocolate milkshake, take off the radiator cap. 4. Fire the bike, as it gets up to running temperature, watch for bubbles in the coolant, especially prevalent when you rev the engine. This indicates a blown head gasket leaking from the combustion chamber to the cooling system (as opposed to the oil passages). 5. If the headgasket is leaking your best bet is to have the head milled, and while your at it, you may as well have the cylinder block milled, since both aluminum castings will "channel out" quickly due to the hot exhaust gas. 6. Run synthetic oil, changing to straight synthetic dropped engine temperature by about 10-20 degrees (without any other changes)! We use Redline or Mobil 1. 7. If your running a "wet clutch" e.g. the FZR and most other bikes, DON'T USE CASTROL SYNTECH, it's great stuff, use it in my truck and all other four stroke equipment,after megatons of hours, they show little evidence of wear on bearing surfaces and cylinder walls. But it apparently has some additives that make it so slippery that we ruined a BARNETT clutch in less than 6 laps at Nelson Ledges and another one at Mid-Ohio.... great for engines but hell on clutch's.... stick with Mobil 1 or Redline and we'll see you at the finish line. Dad
Preston, That bike has a FZR600 rad on it. Was installed by Mark Hurt. You need a bigger radiator like a ZX11 or an older GSXR750. All dyno's don't read the same. And that motor should be getting around 70hp not 78hp.
Did I buy a set of tires from you the night I bought the bike? If you know anyone interested in buying the bike let me know Thanks. YOUR THE KING OF POST
Gave Mark a ZX7R Radiator to go on it, they fit almost perfect. Want to know about FZR 400 ask Mike Troutner
The ZX7 radiator is not an easy install. The ones I mentioned are much easier to fit. Why the hell would anyone contact Trautner, he don't even own an 400.
Tracee, He may have never owned one , can't seem to remember anyone ever beating him on the one he borrowed. Was not fast cause it was Baby Blu
