TE/TC S3 Head on TX300

Just installed an S3 head on my 2017 TX300. Will post a review as soon as I get chance to take a ride. Installation was a breeze. I used the low altitude insert.

Upon inspection after 40 hours, the head looked great, but the piston had some carbon build up, more so than my previous Gas Gas with double the hours. I attribute that to the poor jetting on this bike until I got the JD kit installed.

Took the bike for brief ride and there is stronger power down bottom through mid, kind of like adding a Gnarly pipe. It's not neck snapping but stronger non the less. Had to lower the idle a lot from previous position.

Thanks for the review. What jetting were you running before and after the new head?

Update after some testing had to change jetting, was too lean in mid and top, bottom was fine. Raised needle 1/2 clip and went from 430 to 440 main. Bike ran much stronger but still clean.

I was running a modified JD jetting to start. Before the S3 head was; Blue needle, 30P, 430 main, 3rd clip, AS 3 (JD recommended blue, 30p, 3.5 clip, but 420 main and AS1.75). I do have an open airbox and Moto T reed cage, so that could be the reason for needing richer main than recommended by JD for the stock bike.

Post Head is 30P, 440 main, 3.5 clip, AS3. I had to turn the idle down as well.

The head didn't effect the pilot setting (off idle jetting), but it caused a lean condition in the middle and on top. This was on a 75-80F day. I am thinking when it gets colder 50-60F, I will have to drop to clip 4.

After a couple more rides and the fine tuning with jetting, this is an extremely nice power gain for the money. Better than a pipe in my opinion, as I gained significant bottom and mid without any loss on the top. Putting a GNARLY would have given me similar results on the bottom, but would have made the motor sign off much earlier, putting on a FATTY would have given me more mid and top, but at the sacrifice of bottom power.

The head mod gives you the best of both worlds and I notice the bike runs cooler. I use to feel the heat between my legs in the slow tight stuff, but I no longer feel excessive heat.

For about the same price as a pipe, this is a better mod.

Thank you 95jersey for the info!

I am running the recommended settings similar to yours for the JD kit although I believe for me it recommended 2.5 for the clip at sea level. I do have some "run-on" when I close the throttle although I don't want to lower the idle any further.

Over the winter I may have the head cut by Josh (JBone Motorworks) and will keep your notes for reference. I agree head work is better money spent compared to most add ons. Unfortunately I seem to be inducted into Team Pipe Smasher often and will probably need a pipe by next year. LOL

I just ordered the VForce Reeds and they should be here tomorrow. I am changing these as a precaution before my trip to Michigan in October.

Nice review. Did you measure squish before and after?

no

Hard to argue with that kind of honesty!

You commented that your piston had more carbon build up than your Gas Gas with double the hours... It looks slightly lean to me, although very very close overall. So, the fact that you felt like you needed to enrich the jetting with the "better" S3 combustion chamber... makes perfect sense.

I like the look of that combustion chamber. Has the bathtub shape and the sharp squish band to bowl transition that I am told gives nice performance. Can you measure the squish some time? Curious. Cam.

Just popping in to write a review of the Slavens Mule S3 Head and found this thread. I've been chasing more bottom end ever since I got my '17 TX300. I've gone to a Lectron, and Gnarly Pipe with Turbine Core 2.1 and run AVGas. Like 95Jersey says, adding the Slavens S3 head had a noticeable impact on the bottom end. I kind of feel like the bike doesn't rev-out as far as it used to but I almost never run on the pipe up here in nor-cal. The bike also seems to idle a lot better -- more consistent without a lot of up and down in the rpms. Overall the bike is so good now it's my favorite bike of all time!

I am using a FWW and milled head (1.3mm squish) to increase the bottom end. Very happy with the results and the overrev is not affected. For more bottom end I would have to add a gnarly pipe. As cosmo says it definitely helps the idle, low speed jetting and general runability. Cam.