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XR400 - 440 kit long term longevity

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I've seen this topic pop up a few times, so I thought I would share my findings. Just over 12 months ago I finished off my 440-kitted XR400 that was fitted with brand-new Kibblewhite valve springs, titanium retainers, Wiseco/Hot-rods 400EX crankshaft (love the electric start!), Kibblewhite black diamond valves (standard size) and a stage 3 Hotcam. I used a 4-play 440 kit from eBay that came with a pre-bored cylinder, a Wiseco 11:1 89mm piston and a Cometic gasket set.

 

I had the head reconditioned and fitted with new stem seals and springs at my local machine shop. The head had a very slight mark from the head gasket firing ring so it was skimmed 5 thou, media blasted to clean it up, valve seats recut and then reassembled. Aside from this I did the rest of the assembly myself on my bench, following the workshop manual instructions for setting up the stud heights in the cylinder. I reused my old studs and rockers on the new assembly. I then got the motor running, eventually swapped over to a Mikuni BSR42 and took it out hard trail riding and commuting on the bike as my sole transport for the last 12 months. I have clocked up 260 hours/12,000km on the XR in that time, doing anything from very tight trails banging the bars off trees to hours on end sitting at 110-115km/h (70mph). I average about 5L per 100km (47mpg) with mixed riding as a commuter. In that time the bike was severely overheated once on the trail from hell (we managed 2km in 4 hours), to the point where the oil started to burn and smoke out the breather. It was quite down on compression after that, it turns out it had a partially blown head gasket. It still pulled very hard though! Which brings us to now. These photos are after the head and piston went back into the machine shop for a clean up. Unfortunately I don't have any before pictures due to time constraints except the first one (I am in the process of moving whilst rebuilding the XR). The piston has had a light buff on a wire wheel to remove carbon, the head has been stripped, valve seats recut (they were showing wear - to be expected after 260 hours of use. Especially considering it spent a lot of time >8000rpm!), new stem seals fitted and bead blasted once again. The bore has been honed and was found to be 2 thou out of round. This is somewhat to be expected given how severely it was overheated. Total cost to bring this motor back up to spec was $250AUD including all machine work & a set of rings and it's ready to go for it's next big trip - a 20,000km trip around Australia  :thumbsup: If anyone has any questions regarding building a 440, the electric start conversion or otherwise I'll be happy to help. I'll hopefully have some photos & video of the bike up soon once it has been edited. Night and day difference between a stock XR!

 

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Camshaft is showing a little discolouration but has no scoring or gouges that can be felt by hand - I was expecting more wear than this.

 

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260 hour old piston. Broken in hard! Note: Piston has had a clean before this photo but the skirts are un-touched.

 

 

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Top of the piston after a quick de-carbon. It will be replaced at next tear down.

 

 

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Piston has some marks from blow-by past the rings but isn't showing any signs of fracturing or scoring.

 

 

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Reassembled for round two  :ride:

 

 

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Head cleaned up and ready to refit. I have no idea why one of the valves is a different colour either - it's how I got them from Kibblewhite.

 

So there you have it - 12,000km/260 hours in 12 months. $250AUD and it's ready to rock again. Aside from replacing 2 sets of friction plates I have not had to touch the motor aside from normal maintenance.

Edited by XR Pilot
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We have also had great luck in our 440s,We don't go by hours ,years some over ten years.Ride single track in Baja,.same deal. To go 2 miles, hours.BTR

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BTR - I usually work on a similar line of thinking, it just helped keep track on this motor due to the large amount of riding it has covered in such a short time. For guys that ride every fortnight you'd need to be out for 10 hours every weekend to clock up the same. Your posts were some of the few that actually convinced me to stick with a 440 and go with a BSR42 by the way - and I definitely don't regret it  :thumbsup:

 

YHGEORGE - This might open up a massive can of worms but this motor has spent >95% of it's life on semi-synthetic car oil. I personally haven't had any problems (make sure you stay away from energy-conserving oils with friction modifiers). I think they are Australian-brands but I have used both Gulf Western Oil and Nulon semi synthetic 15-40 or 15/50 with success. My oil change interval also varies, if I have done predominately road riding in winter I'll change the oil out at 1500km-ish (~950 miles) but in summer when it's 42 degrees here (108 deg Fahrenheit) and I'm doing a lot of trail riding I'll drop the change interval down to 300km or so for piece of mind (~200 miles). I'm of the mind that I'd rather use slightly cheaper oil and change it far more often, and with the amount of kilometres I have covered using full synthetic oils changed often would have cost a hefty amount.

 

michigan400 - It would have been more if I didn't have a bit of down time waiting for parts - there was probably a total of 10 weeks or so all up when the bike was out of action. The seat is a stock seat base and foam with an eBay gripper seat cover. Not as bad as an early KTM seat but it's pretty damn firm!

Edited by XR Pilot

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I hear you on riding hours,No need for weekend riding.Its out the front door( Already Dirt) Any day or all days.So 10 hours a week comes easy for me,but I do split it up over 3 bikes.Time on my 97 xr300-98 xr440-07 Wr450 priceless.BTR

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BTR, did you change the counter shaft on your 98 440 to the bigger diameter of the 99's and later?

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BTR, did you change the counter shaft on your 98 440 to the bigger diameter of the 99's and later?

??? I have had a '96, '97 and '01. I have a 16 tooth ctr shaft sprocket that I only use occasionally for DS. I started with it on my '01 and now it is on the '97, fits perfectly. What do you mean?

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In 99, they upped the diameter of the counter shaft by 2mm (I think) because some frisky riders were breaking them.

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In 99, they upped the diameter of the counter shaft by 2mm (I think) because some frisky riders were breaking them.

RE-read my post.

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Copy and pasted from another thread on XR400 model revisions from year to year. It may be listed in the sticky thread as well. Nothing to do with sprocket size.

 

The updates are as follows-
*96- running change made to clutch springs
*97- no updates except for graphics
*98- updated ignition timing, .43 fork springs replace .39 springs, updated damping in forks, updated carb settings ie needle slide jets, stronger kickstart lever, stronger r/h footpeg bracket, stronger rear subframe,updated triple chamber muffler replaced old twin chamber designicon1.png (less restrictive)
99- Identical to 98 save for graphics changes
00- updated countershaft and 2nd gear pinions, updated damping in rear shock, plus fighting red colouring and graphics!!
01 and on- graphics changes only 

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Copy and pasted from another thread on XR400 model revisions from year to year. It may be listed in the sticky thread as well. Nothing to do with sprocket size.

 

The updates are as follows-

*96- running change made to clutch springs

*97- no updates except for graphics

*98- updated ignition timing, .43 fork springs replace .39 springs, updated damping in forks, updated carb settings ie needle slide jets, stronger kickstart lever, stronger r/h footpeg bracket, stronger rear subframe,updated triple chamber muffler replaced old twin chamber designicon1.png (less restrictive)

99- Identical to 98 save for graphics changes

00- updated countershaft and 2nd gear pinions, updated damping in rear shock, plus fighting red colouring and graphics!!

01 and on- graphics changes only 

But, if as stated the the countershaft is 2mm larger in diameter how does the same sprocket that fits my '97 also fit my '01  correctly. What am I missing?

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But, if as stated the the countershaft is 2mm larger in diameter how does the same sprocket that fits my '97 also fit my '01  correctly. What am I missing?

2mm

 

LOL!!! Naw,, I'm not sure man. I think it was on the other end of the shaft, inside the engine, where the failures happened. Or maybe your 11 year old sprocket has worn 2mm and happens to fit perfectly now.  :D

Edited by michigan400

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2mm

 

LOL!!! Naw,, I'm not sure man. I think it was on the other end of the shaft, inside the engine, where the failures happened. Or maybe your 11 year old sprocket has worn 2mm and happens to fit perfectly now.  :D

Yep, only problem is I bought for the '01 which I had before my current '97. Hmmm! Maybe it is a tapered shaft thing with the larger area within the engine. 

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Thanks BTR, thats good to know. But when my motor is tired and I try the 440, I will probably split the case and replace the countershaft and also try to go with 1st and 2nd from the 400EX for a WR version of the XR.

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Thanks BTR, thats good to know. But when my motor is tired and I try the 440, I will probably split the case and replace the countershaft and also try to go with 1st and 2nd from the 400EX for a WR version of the XR.

OK, you got me again. How is the standard not already wr? By no measure could it be considered a close ratio trans. School me.

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I'm running 16/42 and want lower first and second without changing sprockets.

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I'm running 16/42 and want lower first and second without changing sprockets.

Wow, I can't imagine that gearing in CO. You must do a lot of pavement to get to your technical stuff.

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