300HR Ring replacement - 2010 TC250 Husqvarna

I'm just guessing on the correct hrs as I purchased the bike and was told it had ~50 hrs? The meter I installed on the bike shows 252hrs ... Seems I wrote out here I wanted ~300HRs before I had issues such as this with my TC250 Huskies. Seems I made the 300 mark on this bike. But barely ... It was an oil burner and got worst thru time ... Still I though the performance was ok for me and this stock bike, handles very well.

No problems on parts as I've had them for months. Plus just ordered new parts to replace the parts I just used. No problem with new OEM parts for my 2010 TC250 Huskies as shown below. Clutch fiber plates are avail also at ~$109 ...



Same rings fit my 012 TC250 also. Different piston though. Next issue I see coming is do I go with an OEM piston and ring set next (~$250) or go with 3rd party piston and ring set (~$190)... Not sure on another 300HR actually ... I could try just rings again next time but not sure on that yet ...

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I'm more of a foot-peg replacing guy than a inside the engine mechanic so I got my neighbor and Executive C racer friend, Noli, to do most of the work. He saw ~no problems, finished the work, and I rode the bike about 200 yrds home ... Now what?

Here's a few pics ...


The cam lobes are almost perfect ... That bad looking spot on the right side is the light...


Notice that crack in the left side of the engine casing ... Looks like factory ...

Few more ..

Few more...

Here's the interesting one ...

What about that crack along the top side of that crank? Had no answer for that so it's in there ..

Found the words in italics below out on the web ... It's the tail of an engine break-n process and a single response to that processs of breaking in a new engine ...

That process had multiple2x times to start and stop the engine and allow it to cool and that is why the words below reference a dyno as it was included in the break-in process of an entire engine I think.

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The tail-end of this guys' break-in process:

#11- On the second 30 minute ride, at about the 15 minute mark you want to put a full load on the engine—Here’s what is happening inside, All the new parts inside your engine want a easy break in and get to know each other—except the piston rings—they need to work to break in—So now the parts inside are warmed up and happy—now the rings.

#12- During the second 30 minute ride you should have your riding gear on and at the 15 minute mark from a fairly low RPM hold it wide open in second gear until near the rev limiter—this will only take a few seconds—now stay in second gear and let off completely, after the engine gets to a lower RPM, shift up and ride out the rest of the 30 minutes to get rid of the heat you just generated.

You just seated the rings against the cylinder wall and at full throttle with very little oil, when you backed off at high RPM you created a lot of vacuum to pull oil up past the rings and help rinse away very small particles of metal removed during this process.

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The response from 1 person

Heating and cooling an engine does not break an engine in. If “It works fine for me’ or “I’ve never had a problem doing it this way” that’s fine. Keep doing it that way.


The reason to break an engine in is to seat the rings to the cylinder. The ONLY way this is possible is to put the motor under load while accelerating and allow the ENGINE, not the dyno, to slow itself down. The dyno is only there to provide a load during acceleration.

The heat cycle you mentioned isn’t for the engine, its to let the dyno cool down.

The reason for ‘cycling’ from acceleration to deceleration is to force the rings against the cylinder wall, which is done during both these times. Just idling it places very little load on the rings, thus they never really seat. The only thing really accomplished by letting it idle is to wear down those crucial crosshatches that you worked so hard at creating.

The worst thing you can do is to continue to let the engine idle past the point when the engine is up to operating temp. Once it hits that temp, let’er rip. No taking it easy!!! Full throttle loads!!!

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So I went out on hilly golf-course road by my home and rode the new-ringed Husky out and back a couple times accelerating on the uphills and engine breaking on the downhills ... I think this bike is about ready to break-out-Husqvarna-bada$$ ... Its got an ~all stock suspension ...Same way Jarvis rides his Huskies ...

It'll be next week at the earliest before I can start riding\testing this bike and then I can tell if my friends work here has made the bike better than when I got the bike with ~50 hrs and an oil burner already. The starting issue it had when I got the bike many moons ago was fixed and I hope no regressions have happened in that department...

Hope to test this stock suspension against the other ITL TC250s on the SX type track we have here in my ~backyard. One is stock and another has has some suspension work.

I've got about 16hrs on the new rings and no oil burning .. No starting issues .... I'm claiming success ...Not sure if I'll try 300hrs again before the next change ... Might be new piston time next also ... Not sure ... I'm an OEM guys usually with internal parts but they do cost more than the 3rd party stuff ...

I got this bike at 50hrs and it used oil more and more up to the 300hr count ... But nothing else has happened to the bike and its feels about the same (hard) as day 1 for me. Unless something in the head blows or maybe the mains, I don't see why I can't ride this bike lots more with issues kept to minimum ...

This is a wrap ...

How many hours did you have on the ring and piston on your 2008 TXC250? Do you still have that bike?

The 08 TXC250 had ~950hrs on it when it needed to be opened ... That bike never used oil but the big-end bearing when to shedding metal so I went inside it ... The rings and pistons were changed out there at that time with a set I had purchased before from a rider who swapped his out at low hrs for the 300 kit ... After that change, I could tell it had dropped a couple horses after riding it with the newer rings ... I still crank and ride it from time to time here .. It really shows how low-geared these TCs are, ESP with the 14T FS on it... Feels like a street bike to me now. Make no mistake, once that bike is at ~8K on the RPM scale, its fast and has got a good suspension.

This TC bike feels slightly better after new rings on the HP side and really starts better ... No need to crack the throttle as before when kicking it over ... It seems to just start but still needs the TDC kick for whatever reason ... These bikes, including this one, took a real pounding on that issue when they were released. The new eStart on the new engines took a deserved(?) beating also with the worm stuff ... In contrast, the eStart on that 08 TXC worked every time and still works as well as the day I got that bike. Zero maintenance other than batteries ...

I love the bike - like you say especially on the faster flowy stuff where I can keep it in the higher revs. Are others getting that kind of life out of their rings/piston I wonder?

Seemed like somewhere after the 310cc came along, the 250s went underground or something from this site ... might be some 200 hr machines around? ...most seem to be in the 100s .... I'd be scarfing up a few low hr rides for the future if I was back there ...

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My TXC was treated 3x as hard as these TCs ... The TXC was ridden to Manila ... It was pretty dumba$$ of me to do that but after I realized what I was doing along the way, I would never really get the bike over 6K on the hardtop long hauls ending 8-9PM at night lots of days... After this, when the big-end bearing finally needed work, the cause of that was probably due to some hardtop racing I was just doing on another long haul customer ride ... First oil check after that excursion and the filter was full of metal for the 1st time.