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Video: KTM'S CARB VS TPI (TRANSFER PORT INJECTION)

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1 hour ago, SmokeX said:


I haven’t had the need but I am prolly relatively new compared to some I see on here. I hear custom suspension tuning can be really killer.
I like single track technical the most. The one thing I did like about the xcw tpi is the fact that the front wheel comes up real easy. Mine is much tougher it seems and takes more technique imo.

I also like double track and fire roads too to break up the monotony of single track,tight woods riding. So in the summer I end up in the mountains. In the winter down in the valley riding in OHV parks like Hollister Holls and Carnegie.

With all my griping about the TPi bike I still think the concept is cool and what ever to save the two stroke is key if it’s on the chopping block.

We are all brothers of the two stroke scene, and I hope this thread hasn’t caused too many bad feelings.

No hard feelings whatsoever. One thing I don’t like on the xcw is the xplor suspension, I switched it an open cartridge conversion, couldn’t be satisfied   And I just ordered the mx tech inserts, I heard they are phenomenal. I switched up sum shims in my shock and am waiting to test, I’m in Michigan and it’s been a nasty winter.

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1 hour ago, redrider144 said:

I'm glad that we all agree, finally, that carburetors on 2Ts are superior to FI.

Lol, not me. Can we at least agree that 2 strokes are wayyy better than four strokes? Screw those guys! 😂 

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15 minutes ago, Boertmann84 said:

Lol, not me. Can we at least agree that 2 strokes are wayyy better than four strokes? Screw those guys! 😂 

I'm glad that we can all agree, that carbureted 2Ts are waayyy better than four strokes.

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10 minutes ago, redrider144 said:

I'm glad that we can all agree, that carbureted 2Ts are waayyy better than four strokes.

I’m just sorry your missing out on the tpi magic! That’s cool tho, you do you

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26 minutes ago, Boertmann84 said:

I’m just sorry your missing out on the tpi magic! That’s cool tho, you do you

TPI is cool, it's Beta & KTM's oil injection designs that I'm not a fan of.

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No hard feelings whatsoever. One thing I don’t like on the xcw is the xplor suspension, I switched it an open cartridge conversion, couldn’t be satisfied   And I just ordered the mx tech inserts, I heard they are phenomenal. I switched up sum shims in my shock and am waiting to test, I’m in Michigan and it’s been a nasty winter.

I hope the new tech inserts work out for you.

It’s been a nasty arse winter here too. Rain rain. Just about the time it dries out enough to teas me, it rains again. So I’m waiting on that nice moist soil and go ride till I drop :-)

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Hi guys, I'm new here but an old man. i enjoyed this thread and I have a few thoughts to share.

We all know the main reason for fuel and oil injection is to reduce emissions. Direct Injection is difficult, expensive and weighty for a dirt bike. Two strokes sell so KTM will do its best to do EFI/TPI reliably and cheaply to keep the market alive. 

Oil injection has created a future for the 2 stroke. The only way it will survive is if it's normal function removes oil from the intake tract and preferably from the pipe too. Old oil injection systems simply mix oil with the fuel in the carb. I'm not sure about the exact OI function in a ktm but the optimum goal is to send oil to bearings and wear surfaces while trying not to burn it or drip it out the pipe. Oil injection is a godsend for 2 stroke lovers. I remember how bummed and resistant we all were when emissions and 4 strokes took over and most oem's dropped smokers. Thank you ktm.

FI is really good for many riders as they never tune their carb and they run shitty always. I have offered to and have tuned for free. Some don't believe they have an issue. My butt knows there are gobs of power missing. My 450 Honda ran really bad when new. No power until re-jetted - OEM was way lean prob for emissions reasons plus I'm at low elevation.

I've had a few cr 500's (just sold one) and many more bikes but now I have a crf 450x and a 500 EXC. I was waiting for direct injected 2 stokes since 2014 when the corvette got it but instead tpi was released. I do love the many DI advantages. I am now waiting another few years to buy a KTM 3 stroke I read about (est 2023) so I just did a complete rebuild on the Honda. 

My Honda has a carb, the ktm is efi and i love them both - once a carb is tuned and warmed up it runs as well as efi and they do both run awesome - never a sputter and more power than required. The ktm starts a little better when cold but the honda is good too. One thing I had to learn for efi was to keep my right wrist up when in the woops and off throttle - a tiny flick fires - not so with a carb. 

I ride mostly local at -60 to 200 ft elevation and have no carb problems during our trips to NH that peak at 2400. Greater elevation changes could be an issue. If i rode places like others in this thread with 4k' elev changes, i expect the benefits of efi to shine there. I also had no issues with similar 2-3k elevation changes on my cr500 and other carb 2 strokes. Once I tuned a carb on a dirtbike, i have never had to rejet for winter/summer or a 2k+ elevation change. Neither did my friends. I don't race other than scrambles. I bought my first bike in 1969... yep no typo - 50 years behind bars. 

About efi reliability.. it is good but there are many more parts to fail. In a dirt bike I wonder if the most common issue could be the battery. Kick start removal really sucks... you won't see my bikes with a rekluse and no kick lever. Will a TPI bike start with a kick when the batt is dead - really dead... or removed... efi needs juice - would be a great test someone? Maybe that was a supporting reason to delete the kick start - possibly an undeniable benefit to a carb with a kicker? I have replaced countless batteries plus TPS MAP and other sensors in my efi vehicles. They do fail but it's not common. My cbr1000rr will not start if the voltage while cranking is below 11 or so... yes, the efi needs more voltage than the starter! I have fixed carb issues in the woods, more than once. Rare efi failures usually need parts but do not always mean no-run condition.

if I got lost in woods alone with no phone access and no-one around far from home, and I have, I worry about having fuel, not a carb. I currently own 7 efi vehicles and 2 w/carbs. EFI is good... so is a carb - they each have merits and issues.

Most people dislike change by default but the 2 stroke needed new tech to stay alive. OEM's won't race or invest in bikes they can't sell to the public. FI and OI have saved the future for 2 strokes and we should revel in it.

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13 hours ago, ToysAlot said:

Two strokes sell so KTM will do its best to do EFI/TPI reliably and cheaply to keep the market alive. 

Try to find the two mistakes :smirk:

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On 2/16/2019 at 1:02 PM, Doc Brown said:

Try to find the two mistakes :smirk:

Ha! Well cheaply for them anyhow. My 2012 exc 500 has been reliable since new but it's EFI not TPI and OI. Hasn't the TPI been pretty good for its owners? Doc do you own a TPI bike?

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On 2/17/2019 at 1:14 PM, ToysAlot said:

Ha! Well cheaply for them anyhow. My 2012 exc 500 has been reliable since new but it's EFI not TPI and OI. Hasn't the TPI been pretty good for its owners? Doc do you own a TPI bike?

Yeah, the TPI bikes have actually had not been too bad overall.
Of course TPI is getting called out even though it's not FI, but Oil Injection causing most or all of the major issues. I bet things would be much different now if 2strokes got Fi earlier (with or without OI). Heck, I'm sure 4strokes had plenty of issues when they 1st got Fi.

Edited by TheSlayer
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24 minutes ago, Sly_One said:

Yeah, the TPI bikes have actually had not been too bad overall.
Of course TPI is getting called out even though it's not FI, but Oil Injection causing most or all of the major issues. I bet things would be much different now if 2strokes got Fi earlier (with or without OI). Heck, I'm sure 4strokes had plenty of Fi-related issues around 08 or 09, but 4strokes don't suffer from outright engine seizures like 2strokes do when the OI stops working.

What??

I think you will find fourstrokes suffer very quickly and severely when their oil (OI) pump stops, or loses oil pressure. Not just a twostroke phenomenon. 

Edited by uniflow
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Doc Brown, was it you wishing for air cooled engines again, for simplicity?

Thats actually not such a bad request, air cooled engines can be made to operate very well,     with the addition of an ECU fuel control ( electronic fuel injection) but you would have to suffer that other demon, Ethanol. It's an excellent internal cooling agent and will produce more power than petrol when mixed in the right quantities with air. I believe an excelant future fuel. BUT has to have the control of electronics.

Intetesting to note Motobecane (not sure of the spelling, funny little french company) had electronic fuel injection in 1974 on their twostroke road bikes. AND it was a port injection system not TOO dissimilar to the TPI we have now. Pitty they didn't pursue it. 

Edited by uniflow
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9 hours ago, ToysAlot said:

Ha! Well cheaply for them anyhow. My 2012 exc 500 has been reliable since new but it's EFI not TPI and OI. Hasn't the TPI been pretty good for its owners? Doc do you own a TPI bike?

Yes, I had a 250 TPI, one of the first batch delivered in Europe in 2017. But it was a pig. It didnt run well from day one and had the MIL light on from the first start, but no one could say why. After changing the ECU and stuff the MIL was off but I only came about 2 miles than the oil tank cracked and I lost a lot of oil. Was quite a mess but worst was I was on a trip in aforeign country. Had to go home :(

At home I disassembled the bike and what I found was hair raising. Flimsy wiring, bad oil tank design with even worse mounting points, bad design level indicator switch and oil feeding system. The filler neck and hose leading through the frame is alo not a good design and its hard to work on, not technically but it takes forever, nothing you can handle in minutes.

Luckily I had my 300/17 still at the dealer (for sale), it was a lemon too with the crap Mikuni but I picked it up put a Keihin on and was happy with it since. I was fiddling/trying/testing with the Mikuni for about 40 hrs, then thought FI is the way to go as it worked so well on my 350 and my friends 450's but it was a big mistake to compare 4 stroke FI and 2 stroke FI. Its way different and it still doesnt work as flawless as on the 4 strokes.

Of course the majority of TPI runs flawless, but over here there were lots engine failures but it seems to get better.

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8 hours ago, uniflow said:

Doc Brown, was it you wishing for air cooled engines again, for simplicity?

Thats actually not such a bad request, air cooled engines can be made to operate very well,     with the addition of an ECU fuel control ( electronic fuel injection) but you would have to suffer that other demon, Ethanol. It's an excellent internal cooling agent and will produce more power than petrol when mixed in the right quantities with air. I believe an excelant future fuel. BUT has to have the control of electronics.

Intetesting to note Motobecane (not sure of the spelling, funny little french company) had electronic fuel injection in 1974 on their twostroke road bikes. AND it was a port injection system not TOO dissimilar to the TPI we have now. Pitty they didn't pursue it. 

No, I am a fan of liquid cooled engines. But I like the idea. As you say air cooled engines are way better than most people think and they can handle a lot of abuse if the basic design is a good one. Suzuki had good air cooled singles and it had been worth to re-design them but they have got outdated. Same will happen with the carb on twostrokes soon.

I have no problem that people call me a grumpy old stick-in the-mud man. It makes me smile, honestly. I have reached an age where I can say I also have reached a certain level of wisdom. Many technical changes, new things, new materials I have seen coming, some of them going again. Seeing things as a whole is something elderly people like me do, youngsters are fast living so it doesnt matter if a part of a TPI, FI or carbed bike is of bad design and will die soon. They don't owe things long enough to find out that they might be shite.

Coming to the TPI I have a very clear picture. I dont doubt that FI on twostrokes is the future. Saying its because of emission regulations is the biggest BS I have heard so far. But repeating things parrot fashion is an internet disease like superficial knowledge achieved by Google.

Having a well working, reliable FI on a two stroke would be nice. So far I havent seen one but hope I will see one soon. Carbs and FI, both have their advantages but I dont say carbs are outdated and FI is the holy grale. That it is no grale you will learn fast out in the middle of nowhere in a foreign country when your lovely FI bike doesnt want to start. Believe me please I know what I am talking about, there are people who don't ride MX tracks or Enduro parks, who ride through the wilderness of foreign countries.

Unfortunately KTM did not take enough time and living close to them I can tell you that the decision for a transfer port injection was a last minute decision. After 25 years of close friendship with our biggest Kato dealer I got some infos others did not get and I also know and knew a bunch of official factory test riders. Not an easy job btw. However, I do not like the design nor the quality of the TPI components. The filler neck and hose through frame design is one part of it that others have solved way better. Second thing is the low quality super flimsy wiring. I had seen similar bad wirings on 1946 UAZ cars from the former USSR. Horrible and prone to fail, but it will last two or three years till you can beta test the newest KTM race machine, of course only if you pay it.

How's your project going so far? Any news about the patent battle?

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Ha! Well cheaply for them anyhow. My 2012 exc 500 has been reliable since new but it's EFI not TPI and OI. Hasn't the TPI been pretty good for its owners? Doc do you own a TPI bike?

I had the 2012 500 as well, but the XC-W which supposedly had improved fueling/mapping. I liked the bike a lot, but had a lot of problems with the FI system in the 100 or less hours I put on it.

First the injectors clogged. I cleaned them using the YouTube tutorial. It worked for a time (5 hrs or so) and then clogged in the middle of a race and of course it was the furthest away from the pits. FI failure number 1.

I replaced the injector. Everything was great for a time.

Then the fuel pump went while I was in Moab. FI failure number 2. Luckily I was able to tap on the fuel pump and get it running one last time to to get it back to the truck where I had a spare fuel tank and pump so the week of riding wasn’t ruined.

Jump forward one year later and I was back at Moab and the stator went out. Again in the middle of nowhere. FI failure number 3. No stator no FI. Luckily A riding buddy swapped me out his fully charged battery and I was able to ride my bike back to our rental. The bike/battery died less then a hundred feet before getting there and I was able to coast it in.

I know lots of people that have or have had the same bike with no issues... sadly for me that was not the case.

As luck would have it, my brother in-law has the bike now and hasn’t had an issue.

But in my case there were issues and they weren’t fun.

I really like my 2017 XC 300 with Lectron Carb .

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Doc Brown, not sure of your age. 

I was off road riding when the Bighorn was (I was going to write desirable but to be fair I don't think they ever were desirable as such, perhaps only to a few oddballs like me) let's just say I was around with the dirt bike dinosaurs, I too have seen many changes over the years.

I built the first TPI Kawasaki just because I could, being told by many that it wouldn't work, it was a long hard road and I nearly gave up several times. Glad I didn't as this technology was transfered to the TPI YZ. 

The YZ TPI has done a great service, many trouble free hours and many long rides. I can't understand how KTM managed to &%$#@! it up so badly with all their might, after all I had almost no budget to work with, live in a nowhere place😆. The truth is TPI is a worthwhile piece of technology, despite KTM. I'm glad KTM have stuck to the twostroke, when others have abandoning them. I just wished Yamaha had run with TPI, I'm sure they would have made an excellent job of it. 

As I said TPI is just a start, lets wait and see shall we😎.

Edited by uniflow
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On 2/15/2019 at 5:12 PM, Oregon Comrade said:

The same plan you have for your 4x4 when you are wheelin' with your family 30 miles from a road.  The same plan when a stator craps out or your ecu tanks or your put a hole in your case.....lots of bad things happen in the world, I don't have time to worry about it all, judging by your post count, it looks like maybe you do. 

Your are very risk adverse - that's fine, but your speculating on a bike and technology you don't have experience with is a bit obnoxious.  Guys posting pictures of a BETA to support an argument that KTM's are unreliable is very dishonest.  Saying carbs require no maintenance while quoting KTM service intervals for the TPI is disingenuous.

I wasn't sold on the technology, but I actually RODE ONE, it's awesome.  I looked it over closely, it looks like a solid well thought out design.  It ran great, little smoke, no premix to screw with...blah blah blah, all been argued ad nauseam.

Let the guys enjoy em', they are obviously super stoked to have a new bike, whats the sense in being a downer?  I don't get it, but do what you gotta do.

I'm done - I may buy a TPI this weekend....

Comical, mixed with a lack of comprehension or the same kind deceit you claim others have. 

This is a Carb vs TPI thread.  Again check the thread title to make sure I'm telling the truth.  lol

So with that in mind:

Your plan is to treat TPI failure is the same as the other catastrophic failures such as stators.  So tow it out.  OK.  Except that is a failure point carbs simple dont have.  THAT is the POINT.  Again read thread title.

AGAIN you bring up a straw man with the book service intervals.  I pointed out your folly and your STILL using it, very disingenuous.  Go back and read it again...after a bowl of course.  lol

Yes I am risk adverse.  I dont ride in view of the truck, I dont do bunny trails, often times in the desert it gets hot.  ;)  and AGAIN I have seen two pumps fail on one ride.  Heard of others.  Never ever seen a 2s carb fail in all my years of riding.  EVER.  TPI failures should be a concern to anyone who rides remote or solo.  It's why 4s guys who are on top of things replace their pumps and filters at the intervals I mentioned.  Plus if your battery takes a poo on tpi your DONE.  CARB guys do not have to worry about any of  this!!   Read thread title again..... 

AGAIN this is a carb vs TPI (check thread title again and again and again) IF TPI guys dont want to hear mean-e things about TPI I suggest they go elsewhere.  There are some really cool things about them that I and others want.  Just for many of us there just isnt enough there to offset the negatives such as money for parts, time, and possible failure and not to mention the extra weight on a 2s.

TPI guys likely HATE jetting or cant figure it out, likely never ride alone, want a smooth running bike, want the latest gadget, think carbs are old archaic gadgets that should be left in a museum.  I would agree with the carb sentiments.  Jetting is annoying, and the thing seems pretty stupid to me.  Anyone could say anything bad about the carb they wanted and I wont get butthurt at all.   So why so sensitive??

Most guys (the ones that dont get a lemon) seem to really love them, I guarantee you will love yours too.  You just need to read thread titles over and over and over and over and over....................  ;) 

 

  

Edited by Sycamore
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On 2/15/2019 at 5:44 PM, SmokeX said:


It’s had its ups and downs but I too am all of a sudden enjoying this thread. Great info and have learned about some things too.

Hey. One day I might be riding a TPI bike. It will have to come along further, be more tunable, and have the same kind of power and tun-ability my 19XC carb’d bike has now and with the same kind of gear box, fork, and shock that mine has.

Around here the TPI’s are not that big in demand with dealers only getting 3 per year. And even if they were dealers don’t have the supply. That’s selling one every 4 months or something. At least that were true 5 months ago. So even if i wanted one and I didn’t, I couldn’t get one unless I waited months and months or went out of state somewhere.

Same here.  It's got to be better, quite a bit better.  The biggest things people should know about TPI is that all the good it has going for it comes at a price.  You dont jet but you do other things to keep it running reliably.

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25 minutes ago, Sycamore said:

Comical, mixed with a lack of comprehension or the same kind deceit you claim others have. 

This is a Carb vs TPI thread.  Again check the thread title to make sure I'm telling the truth.  lol

So with that in mind:

Your plan is to treat TPI failure is the same as the other catastrophic failures such as stators.  So tow it out.  OK.  Except that is a failure point carbs simple dont have.  THAT is the POINT.  Again read thread title.

AGAIN you bring up a straw man with the book service intervals.  I pointed out your folly and your STILL using it, very disingenuous.  Go back and read it again...after a bowl of course.  lol

Yes I am risk adverse.  I dont ride in view of the truck, I dont do bunny trails, often times in the desert it gets hot.  ;)  and AGAIN I have seen two pumps fail on one ride.  Heard of others.  Never ever seen a 2s carb fail in all my years of riding.  EVER.  TPI failures should be a concern to anyone who rides remote or solo.  It's why 4s guys who are on top of things replace their pumps and filters at the intervals I mentioned.  Plus if your battery takes a poo on tpi your DONE.  CARB guys do not have to worry about any of  this!!   Read thread title again..... 

AGAIN this is a carb vs TPI (check thread title again and again and again) IF TPI guys dont want to hear mean-e things about TPI I suggest they go elsewhere.  There are some really cool things about them that I and others want.  Just for many of us there just isnt enough there to offset the negatives such as money for parts, time, and possible failure and not to mention the extra weight on a 2s.

TPI guys likely HATE jetting or cant figure it out, likely never ride alone, want a smooth running bike, want the latest gadget, think carbs are old archaic gadgets that should be left in a museum.  I would agree with the carb sentiments.  Jetting is annoying, and the thing seems pretty stupid to me.  Anyone could say anything bad about the carb they wanted and I wont get butthurt at all.   So why so sensitive??

Most guys (the ones that dont get a lemon) seem to really love them, I guarantee you will love yours too.  You just need to read thread titles over and over and over and over and over....................  ;)   

Standby to have this all declared "fake news".

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4 minutes ago, redrider144 said:

Standby to have this all declared "fake news".

And that I'm being a downer for people with TPI.  How dare I bring up the realities!  :) 

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