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Only $10 for all 2026 SX, MX, and SMX series.
the SXF is 2013 and the XC is 2009 or 2010
The Shop
Luxon 4-Post Bar Mounts
$189.95 - $239.95
DeCal Works Huge Plastic Inventory of UFO and Polisport kits.
I was sponsored by Michelin, if I hadn't been I couldn't have afforded to even race a 450. Properly.
I may be wrong about one costing more than the other to race. Didn't do the math because It's a pointless comparo. But I'm right about the tires.
1. Topend
Depending on you riding style and usage this varies.
Racing: Ring replacement every 5-10 hours piston replacement every 20 hours that's what I did!
Just riding or not hard racing: add another 10-15 hours to it.
Cost: 80 - 100$ including Gaskets
If you race you need to replace the Piston on a 4 stroke every 6 Race or 15h
So cost will be some how equal work on the 4 stroke takes way longer
2. Clutch
I raced my 125 hard even in deep sand replaced the clutch plates maybe mid season depending on how often we raced in deep sand. No deep sand no clutch work was needed for a season.
Cost here 60$
If you race a 4 stroke it might be the same.
3. Fuel:
Yes if you race hard a 2 stroke will need more fuel in theory 100% more but that's not correct.
I found about 30% more compared t a 4 stroke.
Here you do have an advantage with the 4 stroke less fuel and no premix
4 Engine Oil change:
Not needed due to premix!
4 Stroke could be sort of expensive.
Change every 10-15 hours
Cost:
10$ per Filter
5-8$ per oil filling.
Lets assume you race Hard both bikes the 250f will cost more
If you just ride it will be somewhat equal!
Maintenance:
Some say a 4 stroke doesn't need that much maintenance like a 2 stroke. (Topend,Clutch aso.)
That's not true by ignoring the fact that you have to do the same work on a 4 stroke it doesn't mean you don't have to do it.
Lets see the recommended Service intervals CR125 and CRF250R
Piston:
Replacement
125 3 races or 7,5 hours cost 100$
250 6 races or 15 hours cost 230$
Transmission Oil:
125 3 Races or 7,5 hours
250 6 races or 15 hours
Engine oil including filter:
125 not needed
250F 6 races or 15 hours
So from my point of view the discussion is useless about running cost will be somewhat equal.
The amount of work which needs to be done is more on a 4 stroke.
Especially the Topend is not complicated just takes way longer.
I can change a piston of a 125 in less than 30 minutes means even between Moto's what I did sometimes.
A 4 Stroke needs way more time, did it on my CRF250R sometimes and it always takes 1-2 hours to make it right.
https://www.facebook.com/TwoStrokePerformance/photos/pcb.83996759940387…
Dyno Vid
https://www.facebook.com/video.php?v=836232929777343&set=vb.28330891840…
Will cost about 500 - 600$ and most tuner can do it in 1-2 days.
If they use a flow bench it might take some more days.
The good pat is the power valve it can make the power band way better than in the 70's
If you check the links and go to his facebook page. He's built some rippa 125 engines. That's who builds mine.
Here you go. 125 Dyno results.
https://www.facebook.com/TwoStrokePerformance/photos/a.284879841579324…
He loves the Whizz Bangers.
Pit Row
Don't suck, sook and leave ya Wombat (Eats, roots and leaves).
While he is one of the more budget friendly options, Porting/ head mods for a 125 from Eric Gorr is $200. http://www.goforwardmotion.com/2Strokes.php
And a pipe and silencer, if you choose to add them, is about $300. Many prefer the stock since there isn't much to gain from a pipe.
Piston kits would still only be the average $100-$150. If you are doing 100 hours over the season I would say 4-5 piston/ring changes would be in order. So we will say worst case scenario of $750.
If you are blowing out cranks under 200 hours you really need to look at your air filtration and choice/ratio of premix. By then most racers would have sold the bike and bought a newer model.
That puts us at a total of $1,050 for engine build/ maintenance over the course of a race season (assuming 100 hours).
I'm sure someone will hop on and give some other ridiculous numbers but this is a pretty solid estimate with many variables involved though.
Here is what is happening in my market. I have brand new 125's to sell. One of the ones that you posted a photo of. They don't sell very well.
Next, our state series has a 125 two stroke only class and every year the promoter has to make the hard decision on weather or not to keep the class around. Not enough entries. I hope it is better this year because I am making my kid race it.
It sucks but I see first hand a good reason why there are only a few manufactures participating.
Doesn't matter if 125 or 250 2 stroke you will never have similar torque compared to an 250f.
The engine design is way different. But you can gat quit close.
Which was my entire point. Yes , it's still going on at almost every track but the choices are limited . I always thought the 125 class was the most important step for kids moving up. But to be competitive now days they have to jump on a highly modified 250F.
I didn't mean to sound like a dick ( so sorry about that ), but on moto boards you are going to get 2 stroke fans , and guys that slam on the dudes who like them. Hell....I ride both too , they both have their place. But killing off the 125 class ( for the most part ) in my eyes , was a crime against the sport.
I will tell you how it is because 19k from a 125cc kart is bullshit and you know it, unless your delusions are taking over again. I have two friends who race the direct drive air cooled bastards that are screamers and they turn closer to 15.5k....their 125 shifters went to 11.5k and that was with their TM. The Pavesi (spelling?) was closer to 10.8k.
Edit : Upon a bit of research I see the F100 karts can run up to 19k...still not a 125 that you claim never has to be rebuilt
125
250 ( 2 and 4 stroke)
Open
Back when these classes were recognized and raced at the national level, not all of them ran the entire season. The 125's and open bikes split the season if I remember correctly. Face it, there are guys who have refused to race SX and outdoors because the schedule was too damn hectic. The 250 SX classes are split regions and only do half a series. Maybe the 125's and 450 class could do half an outdoor series and keep the top guys competing a little longer. Who knows, just a thought ....
Do a common class rule and let the 250F and 250 smoker be options for the big class. I don't think that we need modern thumpers to totally disappear, but the 450F may have to go the way of the 500cc smoker.
We had a CR 125 Shifter that ran at 14,500.
You run more like a % of oil though. Around 16:1 it comes out to.
But thats relative to say a low revving 500 only needing 60:1
Post a reply to: Everybody agree the 125 class is badly needed?