TE/TC RK Tech head

Just installed a RK Tech head to my 17 TE 150 and made great improvements in performance but I’m getting a slight knocking. I️ ordered one for sea level and pump fuel, should I️ use a mixture of race gas and I’m using 18 jetting.

VP T2 and your done

Don't even have to bother with ethanol gas and fuel stabilizer.

I would be interested to hear your comments on how the RK Tech head works on your 150. I've got one and need to quit procrastinating and get it installed.

Honestly the bike was improved especially when you lug it through slow technical stuff and climbed hill better, but I️ heard a slight pinging at low rpm’s. I️ also installed a V Force 4 at the same time so I️ really can’t tell if one helped the other mod. I️ picked up a can of VP fuel and I’m gonna see how that improves things .

Great to hear an "RK head on a 150" report. We've got three 300's in my group running the RK. On my 150 I have a stock head shaved for .036" squish and it, too, was a significant improvement. Still testing 30 vs. 32.5 pilots, but otherwise running 5.0 slide, S-4, 43-74 middle, 520 main.

My jetting is 30 pilot. 470 main 43 74 2nd grove S4 stock slide and no air box mods and I’m gonna go 1gallon of VP14 with 3 gallons of 94 pump gas at 60:1 and should kill the detonation.

With RK Tek head in 150 I’m running 42.5 pilot, 520 Main, 4374 clip # 3 S1 needle jet and 5.75 slide. Being able to run clip 3 makes a huge difference with these 150’s. With stock head that’s just not possible whatever jetting combination is tried. I’m at sea level. Tried S4 but reverted back to S1. I’ve opnened up air box too.

Are you running pump gas? Quite a jet difference and amazingly both our bikes probably run great.

With the RK Tek head I had to richen the Lectron almost 2 turns from where Dave had me set it for the stock head. I also get better mileage with the richer setting. Just more bottom/mid torque.

Yes pump gas. As temp is dropping, tried the richer stock 4.0 slide with RK Tek head - dropped pilot to a 40 and went 1/2 clip Leaner on needle to 42 74 clip 3. For winter, think this is a better set up.
Have also revered back to stock pv spring ie the progressive one.

Tested the bike with VP race gas,1 gallon to 2 gallons of pump gas and absolutely ran perfect but now I lost the rear brakes, must be a bad bleeder because when I️ checked it it just snapped off, there was a small scrape next to it so maybe a rock banged it . Ordered a Tusk banjo bleeder and hope that’s it.

Kinda looks lean, any suggestions, maybe go richer on main?

As it is a 150 you spent more time at 1/2 to full throttle so I would suggest 2 up on the main, then work your way down if it is rich. Healthier for your plug to be a fluffy dark brown. Cam.

Yes, go up! Did you notice that many of us are in the 520 main jet range? Mine was pretty lean down near 470.

Just went up to a 480 from 470 and will go up one more , might need a break due to sore ribs, had one of my famous falls when I’m parked on a side of hill with the engine off and my 5 6” frame lets me down and I fell over and my ribs where the chest protector doesn’t cover landed on another parked rider and he fell over and down the next part of hill. Domino effect and a cracked rib or 2.

Get better!

Ya, really sorry to hear that. But don't think that's an excuse for delaying your ride reports!

I finally got my RKT insert installed last night. The pic shows the difference in the combustion area, definitely looks smaller on the RKT insert. The plug had good color around 3/4's of the electrode and was sooty on the other 1/4, a bit browner than the plug pictured above. It ran pretty good but it looks like my jetting could have been a bit leaner. I typically ride tight single track so I'm not going around at high rpm very often or long. Currently 470 MJ, lean needle from the Husky supplied kit with the clip at the top or second to top (I can't remember without looking at my log book), 37.5 PJ, yellow PV spring 2 turns in from flush, float height at ~8mm, AS 1.5-2 turns out (again I have to look at my notes).

I'm waiting on new a V Force reed assembly before I get to try out the new head. I am thinking of going back to stock jetting and starting over from there with the new insert and reed block. 1000-3000 feet, 45-55 F at the moment, 92 octane non alcohol gas, 60:1 Motorex. Any input on where to start with jetting would be appreciated.

Edit: oops I see some jetting recommendations above. I think I'll try the 490 MJ (because that's the biggest I have at the moment), 40 PJ, stock slide, leaner needle at clip 3.

I’m running a 500 main but I haven’t tried it yet and a 30 pilot and the rich needle from the kit.