TPI Fuel Injector Relocation Block | How it Works
For 2020 - 2023 KTM, Husqvarna & Gas Gas Bikes
Pictured here is a factory KTM throttle body for 2023. It's a bike that was being taken apart at the 2021 Tennessee knock out race.
It's a nice thing to see, because the mechanic working on the bike, confirmed to someone I know, that they re tired of the bikes destroying top ends, and lawsuits, so they moved the injectors to in front of the reeds.
SO.... If you think that our idea of relocating the injectors doesn't have Merritt......... Well, you may be one of the few. Save your money though for rebuilds though, while being cynical. You'll need it.
Even KTM recognizes that
So, we made a simple, intelligent fix, for the bikes with both of the injectors in the cylinder. We made a special reed block that lets you relocate the injectors from the cylinder ports, to the area between the throttle body and the reeds.
Just like the pic you saw above, where the 2023 KTM race bikes put them.
Above you see the dyno chart between the stock set up and the Relocation block using the split kit. The power valve was also turned 2.5 turns out from stock. With the mixing of the air and fuel, from 2 different locations, it's nice to see the burn pattern on the top of the piston is still so symmetrical.
What you see below is after 16 runs on the dyno, on top of a cleaned piston top. It's a very symmetrical burn pattern, which means nothing weird has happened in the mixing of the injectors, and no power loss has occurred because of that.
It's always nice to "note" what you are doing. Even if the ink is a carbon burn.
Benefits of this Injector Relocation Kit are:
1. No more engine destruction in a short time.
2. Better power through out.
3. Stronger power bottom to top
4. Snappier bottom end
5. Higher and better idle
6. No more engine destruction in a short time
Probably the easiest way to describe what the moving of the injectors, or one injector does. These are pics sent in from a guy who was out in the desert with his friend.
His friends cylinder is on the right. The destroyed one. It had a TSP head, reprogramming and FMF 2.1 muffler.
A you can see, it seized as solid as a bike could possibly seize.
The other guys bikes cylinder is on the left. He had our relocation block on, still used the stock oil injection and added another ounce of oil per gallon of gas in the tank. He had had the kits with the filter and high flow tank fitting, the reeds and our Spark arrestor. He said he sent these in to show that our ideas and what we said was indeed correct. He said....
"My friends bike seized up hard, causing him to crash. My bike was not only hauling ass compared to his, but it had to pull his all the way back to camp. He pulled his apart and this is the pick. I then pulled mine apart and this was my cylinder. It looks like there is more oil in there though because I wiped it clean with an oily rag. Just to see what the rag looked like.
Funny thing was, that there was a ton of oil inside his reed cage. I realized everything you said to me on the phone just came true. The lack of vacuum at higher throttle openings won't pull the thick oil in there, and the bike will just be running on pure gas. And gas has zero lube to it.
I can't tell you how glad I am that I listened to you and that it made sense to me. Now he's waiting 8 months for a cylinder and crank. Look at how good mine looks. It was faster than his right away as well. Thanks for doing what you do".
John. H, San Diego, Ca
The pic above helps explain it all in the easiest fashion. Stock, you have the 2 injectors going into the cylinder. You see the one in the cylinder here. The injectors just spray nothing but gas in the cylinder. Gas has NO lubrication properties.
The oil to lubricate the complete bottom and top end, is vacuum fed into the throttle body. The oil is just oil now, and it's thick and moves slow. It has to get sucked into the engine with engine vacuum, to get to the crank and then into the upper cylinder.
And the oil does it's best, to not get into the upper end of the cylinder any time soon, as it's stickiness, stick it to the inside of the fluttering reeds and then the surfaces of the transfer ports.
And this situation has the bike running the whole time, on pure, un lubricating gasoline, with no oil in site. Until it finally works it's way through.
And if you want it to get worse, it does. The more the throttle is open, the less vacuum there is in the engine, to actually pull the oil in. That's the real reason the one pic above is so destructive. He was at higher throttle openings. This made the reeds flutter so fast, that the lack of vacuum in the engine, just made the oil get kicked back into the reed cage.
But when we move one or both of the injectors between the oil feed and the reeds, well then everything can blend together and work as one again.
Just like any carbureted 2 stroke, that runs forever, the air, fuel and oil can all mix together in the reed cage and move through the engine as one.
Then, when the gas has worked it's way through the engine and made it to the spark plug to ignite, it's had oil with it as well, lubricating all the parts as it goes.
It should be pretty obvious at this point, why leaving these stock is a bad idea
Obviously your thinking, Why were they even built this way? The answer is, to be able to pass emissions in Europe. Quick failure is just a cost of doing business.
Below, you see the newest of the new advancements,
The "INJECTOR SPLIT KIT"
I know exactly what you are thinking. If you have gone to all of this trouble to get the injectors out of the cylinder, then why would you put one back in? Well the main reason is that it helps tone down a bit, the extra snappy bottom end, that the injector block adds.
As of 8-21-22, there have been just over 700 of these blocks sold. There are not many complaints, but when there are, it is always the same thing. " The bottom end is TO responsive, for my tighter single track riding.
SO, we decided to split the difference. One injector in the block, still gives you the fuel you need to help dissolve the incoming oil and move it through the engine. And the other injector being back in the cylinder ( as long as some oil is added to the gas in the tank ), helps smooth out the extra power and response the block gives you
The injector split kit, has been tested by a good number of people before it came to the public. And the public that bought it, before it came to this writing agreed with the testers.
"If you are and enduro rider, it's the way to go".
"It gave me that tractability I was looking for. Better power than stock, but better control than all the power just the block gave me".
"You couldn't have any better power for extreme enduro in Hawaii. The split kit, 11 oz clutch weight and power valve flush with the case. Mahlo my friend. Mahalo"