98 WR400 hard starting

[u10b_coach]

I am one of those lucky people that has had no problems with my 98 WR 400. I clean the airfilter, change the oil and go. The bike has not seen the inside of a shop since I bought it. That may be catching up to me.

The last outing it was a different beast. It was hard to start, gas foulding a plug to start. Once I did get it running it ran for approx 45 seconds with me holding the throttle about 1/2 throttle when I noticed the head pipe was glowing red. I had never seen this before.

After we took off it ran normal until we would stop. It stalled easily and required I use the hot start button EVERY time I went to start it. This was very uncharactorist behaviour for this bike.

Any ideas? Could the valve adjustment be causing the starting issues?

[Matty05]

When was the last time you started your bike?

If you leave your bike in the garage for a while, drain the carby of fuel first, or the "heavy" fuel will foul your plug and the bike will really struggle to start.

Change out your fuel to fresh stuff and she should fire.

You should already be checking your valves every 6 months to a year, give them a check, but I bet you it is fuel.

[The_Missile]

Checking valve clearance is also obviously a good place to start.

But also, preventative maintenance......the older models of the WR400 suffer from broken carb slide syndrome. What happens is the bottom corner(s) of the carb slide slowly crack and ultimately the corners break off. Before it completely breaks you will get erratic behaviour on idle and other nonsense. If you have never checked this, check it now - you have to remove the slide to find evidence of cracks (use a stong light & magnifying glass if necessary - and yes even such small cracks will affect the response. You want to avoid having a chunk of slide make its way into your engine......

It would also be a great time to check / clean the whole accelerator squirt mechanism for rust grunge. Do the "taffy mod" on your accelerator squirt duration. I presume you are deoctopussed too ! If not check out the de-octopussing threads. PS I am being serious....use search to find the relevant posts (oooooooold) on the above.

You have to remove the carb to do that so no (not much) extra work if you are also doing the valves.

[u10b_coach]

When I park the bike I close the fuel petcock and let run the motor till it dies. The fuel in the tank is treated with Stabil if I think it will be parked for any period of time.

I will drain the tank and start with fresh fuel.

I will also inspect the carb slide.

I have no idea what deoctopussed means. I will search the threads for this one.