Bringing the passion and performance back to 2 strokes...

KTM EXC and SX

 

KTM85 2017

KTM85SX

Most popular setup:

For the models up to 2017 the most popular setup is to machine the head, bore and rejet the carb, set the ignition advance to our TSP spec and fit a new pipe. This simple setup gives good gains to power everywhere. If you really want a winning engine then ask us about our Pro Build which produces approx. 28rwhp.

For the 2018-on models fit a new TSP head insert (raised cyl height for MX), Athena GET ignition, bore the carb and rejet, and fit an HGS pipe. This simple setup gives good gains to power everywhere. If you really want a winning engine then ask us about our Pro Build which produces approx. 28rwhp. 

Jetting:
2013-2017: 42 pilot, N5HH needle 2nd clip, 120-125 main, AS1.75.  Stock main jet is too lean and pilot/needle setting are too rich.

2018: stock jetting is fine for a stock bike. For enduro or trail riding the pilot and/or needle can be leaned off slightly to reduce bog out of corners. Properly modified bikes will need to go up 2 or 3 sizes on the main jet.

These are ballpark specs only, for stock or lightly modified bikes. We do not accept any liability if you choose to run these specs.

Head:
2013-2017: Run a TSP head for more power everywhere over stock and less risk of detonation. See SHOP for prices and details. Our heads perform better and cost less than anything else on the market.

2018: We offer TSP head inserts which fit into the stock outer parts. These give more power everywhere and less risk of detonation. See SHOP for prices and details.

Carb:
Carb boring adds extra mid/top end performance. Bore size is critical, going too big will make jetting difficult. See SHOP for prices and details.

Porting:
Don’t bother for trail riding or club level MX. For serious racers we can get a lot more mid/top power with correct porting. Beware that most ported cylinders we see are done incorrectly and make very poor power. The old saying “less is more” applies to this cylinder! See SHOP for prices and details.

The 2018 models have much less top end power than previous years, making about 23.5rwhp on our dyno compared to approx. 25rwhp for a 2017 model. We can increase power up to around 28rwhp on the 2018 models with no loss of bottom or mid by doing careful porting. Without good porting there is no way of getting these bikes up to this power level and no amount of expensive bolt on mods will come close.

Exhaust:
Stock system is fine for trail riding and club level MX. For more serious racers we suggest an HGS, DEP, or FMF. All of these add extra top end power. The stock silencer is absolutely fine for all levels of racing. Adding any of these pipes to a badly ported cylinder will make LESS power everywhere.

For the 2018 models we can make around 28rwhp using either the stock or the HGS pipe.

Ignition:
2013-2017: The SXS CDI will cause a misfire at high rpm when combined with a properly setup head. We can get much better results by using the stock CDI (with an updated timing spec in mm BTDC) combined with our head design. When you buy the head setup we will give you the new timing spec for free… the end result is more power everywhere for less cost!

2018: We strongly suggest an aftermarlet ignition for the 2018 models. When tuned properly they make much more power than the stock CDI. We sell the Athena GET CDI loaded with our custom maps in the SHOP. When combined with a properly combustion chamber design it makes a huge difference to power.

Rebuild intervals:
Top end: Every 30 hours for trail riding/club MX. Every 10 hours for A grade MX

Bottom end: Every 100 hours for trail riding or club MX. Every 40 hours for A grade MX

Fuel/Oil:
Run 30:1 for A grade MX and 40:1 for trail riding. Normal 98 unleaded is fine for a stock engine and for our modified engines. “Race” fuels generally wont add extra power to a good engine setup, but they will be more consistent in quality. They may add extra power to a badly setup engine.

Suggested Mods (in order, first to last):

– Head setup (all years)

– Rejet the carb (2013-2017)

– Ignition (either Athena GET for 2018 or TSP ignition timing spec for earlier years)

– Different pipe (usually HGS)

– Carb bore

– Cylinder porting

– Case mods and reed setup

– Everything else…. ceramic bearings, superfinished transmission, crank inertia, etc… all these mod add LOTS of cost but not much performance.

Notes:

We have done a HUGE amount of testing and development on these engines and have come up with a range of packages to suit novice through to national level riders.

Off the showroom floor these engines can vary a lot from one bike to the next. Although average stock power is around 24.5-25 rwhp on our dyno (2013-2017 models) we often see power on a stock bike varying anywhere from 24-25.5hp at the rear wheel with big differences in midrange power. This means some bikes are much slower than others which can lead to a lot of frustration from riders and parents wondering why they are much slower than the competition.

This is one engine where it is VERY easy to lose power if you dont know what youre doing. We have seen countless bikes come over our dyno with cylinder porting and all the latest bolt on mods making less torque than a stock bike. The old school methods of porting do not work well on this engine and often result in a loss of power. In order to get the most out of this engine it needs to be set up VERY carefully and a range of key changes need to be made.

After hundreds of hours of dyno testing we have developed a range of mods and packages which dramatically improve this engine.

2013-2017: Make sure you change the stock jetting as the main jet is too lean. These engines are tough on bottom ends and it is common for them to fail, especially on a stock bike with stock jetting. Our modified engines have excellent reliability and make much more power everywhere than a stock bike. Don’t fall into the trap of buying all the usual expensive bolt on mods (high inertia cranks, ceramic bearings, superfinished transmissions, etc)… weve dyno tested lots of bikes with these mods and they hardly make any difference. We can get much better results by doing sensible mods to the stock parts, saving you a ton of money. Of course if you want these parts we can supply them but they only apply to the highest level of racing in our opinion.

2018: The only way to make big power with these is with good cylinder porting, head setup, an new ignition, a carb bore and possibly a new pipe. These 5 mods make all the difference and any other mods beyond this will give diminishing returns.

 

 

 

KTM125 2017

KTM125SX, 150SX, 150XC-W and 125EXC:

Most popular setup:

For the models up to 2015 the most popular mod is to setup the head. For 16 – on models setup the head and fit an Athena GET ignition (see our listings for Power Kits).

125 Jetting:

up to 2015:

2016: 45, N1EF clip 3 or 4, 180-182 main

2017: 40-42.5, stock needle 3rd clip, 480 main jet, AS2.0

2018: coming soon

These are ballpark specs only. We do not accept any liability if you choose to run these specs, however we have safely used them on a number of bikes.

150 Jetting:

up to 2015:

2016: Specs coming soon…

2017: 40 pilot, 43-74 needle 2nd clip, 490 main jet, AS1.50… this was on a bike that made 46rwhp with head setup and porting, all other parts were stock.

2018: coming soon

Head:
All years: Run a TSP head for more power everywhere over stock and less risk of detonation. See SHOP for prices and details. Our heads perform better and cost less than anything else on the market.

Carb:
All years: Stock carb size is good for huge power. Boring the carb can be done but it is down the list after head setup, porting, exhaust, etc.  See SHOP for prices and details.

EXC models have a 36mm carb. This can be oval bored for more mid/top.

Porting:
2016 on: Don’t bother for trail riding or club level MX. The cylinder casting is excellent and doesn’t need tidying up, however we can change the ports for more mid/top power.  See SHOP for prices and details.

up to 2015: The cylinder casting is rough and needs tidying up. We can either do a basic clean up of the cylinder or we can change the ports for more mid/top power. See SHOP for prices and details.

Exhaust:
All years: Stock system is fine for trail riding and club level MX. We can get a lot more power from these engines by doing advanced porting and head setup only, still keeping the stock exhaust system.  For more serious racers we suggest an HGS, DEP, or FMF. All of these add extra top end power. The stock silencer is absolutely fine for all levels of racing. Adding any of these pipes to a badly ported cylinder will make LESS power everywhere. If you are looking at porting the cylinder for extra mid/top then we suggest keeping the stock exhaust until after the mods are done.

Ignition:

up to 2015: Stock CDI is fine. EXC models have a softer ignition curve. Fitting an SX CDI is a good choice for more power everywhere.

2016-2018: An Athena GET CDI with our custom ignition curves and a TSP head insert will make a huge difference to power throughout the rev range.

Rebuild intervals:
All years:

Top end: Every 40 hours for trail riding/club MX. Every 15 hours for A grade MX

Bottom end: Every 150 hours for trail riding or club MX. Every 60 hours for A grade MX

Fuel/Oil:
Run 30:1 for A grade MX and 40:1 for trail riding. Normal 98 unleaded is fine for a stock engine and for our modified engines. “Race” fuels wont add extra power to a good engine setup, but they will be more consistent in quality. They may add extra power to a badly setup engine.

Suggested Mods (in order, first to last):

2016-2018 models

– Head setup (TSP head insert)

– Rejet the carb

        – Athena GET CDI

– Cylinder porting

– Different pipe

– Everything else…. ceramic bearings, superfinished transmission, crank inertia, etc… all these mod add LOTS of cost but not much performance. These are only suited to the highest level of racing.

up to 2015 Models

– Head setup

– Rejet the carb

– Cylinder porting

– Different pipe

– Carb bore

– Everything else…. ceramic bearings, superfinished transmission, crank inertia, etc… all these mod add LOTS of cost but not much performance. These are only suited to the highest level of racing.

Notes:
The new 2016 125/150 engine is very well designed and makes huge power for a stock 125. Best mods for 16-18 are head setup and an Athena GET CDI (adds ~2hp up top and nice gains through the mid) and some sensible cylinder porting. The stock cylinder casting is very good and so theres nothing to be gained just by cleaning things up. If you want to get even more power you’ll need to do advanced porting (altering port heights/widths) to get improvements to mid/top power.

These engine produce big power for a 125/150 so stay on top of your maintenance and rebuilds to avoid expensive failures. Our modified engines have excellent reliability and make much more power everywhere than a stock bike. These engines respond extremely well to simple work… keep the stock CDI, carb and exhaust and just setup the head and do some mid/top cylinder porting for an extremely competetive bike…

The KTM 125 engine up to 2015 is very strong and responds very well to some sensible mods. The overall cylinder design is good but there are lots of casting issues that can be cleaned up to improve power everywhere. Also, careful powervalve setup is critical to getting the most from this engine. The EXC model shares the same basic engine but with a softer ignition curve and smaller 36mm carb. This engine hardly changed from ~2000 onwards. They are generally very reliable for a 125 and respond extremely well to simple work although they will never make the same power as the newer models.

 

 

KTM200 2016

KTM200EXC:

Most popular setup:

The most popular setup for this model is head setup, carb oval bore and rejet and our ignition mod (on electric start models). You can also add a reed cage spacer for a bit more mid/top. This setup gives more power everywhere, especially bottom/mid, better fuel economy, smoother power delivery and theres no risk to reliability.

Jetting:
38 pilot, N1EI needle 3rd clip, 165-175 main, AS1.75. Main jet depends on mods and riding conditions. Stock main jet is too lean and pilot/needle setting are too rich.

These are ballpark specs only, for stock or lightly modified bikes. We do not accept any liability if you choose to run these specs.

Head:
Run a TSP head for more power everywhere over stock and less risk of detonation. See SHOP for prices and details. Our heads perform better and cost less than anything else on the market.

Carb:
Carb oval boring adds extra mid/top end performance.  See SHOP for prices and details.

Porting:
Dont bother for trail riding. For racers we can get a lot more mid/top power with correct porting. See SHOP for prices and details.

Exhaust:
Stock system is fine for trail riding and most forms of offroad racing. For more serious racers we suggest an HGS, DEP, or FMF. All of these add extra top end power. The stock silencer is absolutely fine for all levels of racing.

Ignition:
The stock ignition curve is fairly soft. Our ignition mod adds ignition advance across the board and gives more power everywhere (suitable for electric start models only). For kick start models you can advance the stator plate by a certain amount… this is only suitable when running one of our heads and correct jetting. We can give you the new ignition specs when you purchase the head setup.

Rebuild intervals:
Top end: Every 70 hours for trail riding. Every 40 hours for offroad racing.

Bottom end: Every 200-300 hours for trail riding. Every 100-150 hours for offroad racing

Fuel/Oil:
Run 40:1. Normal 98 unleaded is fine for a stock engine and for our modified engines.

Suggested Mods (in order, first to last):

– Head setup (adds more power everywhere, especially bottom/mid)

– Rejet the carb

– TSP ignition setting (we give you this spec free with the head setup, adds power everywhere, especially bottom/mid)

– Carb oval bore (adds mid/top)

– Reed spacer (adds mid/top power)

– Cylinder porting (adds mid/top)

You can do all these mods at once or add one at a time.

Notes:
The KTM200 EXC engine is basically a bored and stroked 125 with a relatively soft power delivery for offroad use. There is loads of potential for more power from this engine if the right mods are done. The minimum that should be done is setting up the head correctly to give much better bottom-mid without losing anything up top. The cylinder casting has a lot if issues that can be easily fixed to give more power everywhere. The 36mm carb can benefit from an oval bore for much better top end. We’ve seen several KTM200’s leave the showroom floor with as little as 30rwhp. Sensible mods can see it make over 41rwhp without any loss of reliability… much more power can be made if you add advanced porting to this setup. The stock exhaust is fine.

For electric start models we strongly suggest adding our KTM Ignition Mod for even better power throughout the rev range.

 

 

 

KTM250 2017

KTM250EXC and 250SX (carb models):

Most popular setup 08-16 models:

The most popular setup for this model is head setup, carb oval bore, rejet carb and our ignition mod (EXC only).  This setup gives more power everywhere, especially bottom/mid, better fuel economy and much smoother power delivery with no risk to reliability.

Most popular setup 17-on models:

The most popular setup for this model is head setup, carb slide mod, rejet carb and our ignition mod (EXC only). This setup gives more power everywhere, especially bottom/mid, better fuel economy and much smoother power delivery with no risk to reliability.

Jetting:
2008-2013: 38, NECW or N2ZW clip 3, 168 main, AS1.75

2014-2016: 40, NECW or N2ZW clip 3, 170 main, AS1,75

2017-on: 30 or 32.5 pilot, 43-75 needle 2nd clip or 42-75 needle 3rd clip (1/2 clip richer overall), 450-460 main, AS1.5-2.5, TSP modified slide, float height 8.5mm. These specs work best with our head design… together they completely transform the bike. Slide mod is a must if you are going to keep the Mikuni carb. Otherwise swap to a 38mm Keihin (see SHOP).

NOTE: the 2018 bikes came with completely different carb specs (needles, emulsion tube, pilot jets, etc) to the 2017 models. In order to jet a 2017 model properly you will have to buy the genuine KTM updated 2018 jetting kit. We stock these and can supply one with your slide mod if necessary. We also include a couple of extra jets in the kit to make them suited to a wider range of conditions.

These are ballpark specs only, for stock or lightly modified bikes. We do not accept any liability if you choose to run these specs.

Head:
Run a TSP head for more power everywhere over stock and less risk of detonation. See SHOP for prices and details. Our heads perform better and cost less than anything else on the market.

Carb:
2008 – 2016: Carb oval boring adds extra mid/top end performance.  See SHOP for prices and details.

2017-: Stock carb size is fine.

Porting:
All years: Dont bother for trail riding. For racers we can get a lot more mid/top power with correct porting. See SHOP for prices and details.

Exhaust:
All years: Stock system is fine for trail riding and most forms of offroad racing. For more serious racers we suggest an HGS, DEP, or FMF. All of these add extra top end power. The stock silencer is absolutely fine for all levels of racing. If you want more power spend your money on head setup first and rejetting first… its much better value for money.

Ignition:
The stock ignition curve is a bit soft. Our ignition mod adds ignition advance across the board and gives more power everywhere (suitable for electric start models only).

Rebuild intervals:
Top end: Every 80 hours for trail riding. Every 60-70 hours for offroad racing.

Bottom end: Every 300-400 hours for trail riding. Around 200 hours for offroad racing

NOTE: it is very common to get dust through these engines even if you are careful with your filters. This can reduce engine life dramatically… we see lots of bikes with less than 50-100 hours needing full rebuilds.

Fuel/Oil:
Run 40:1 or 50:1. Normal 98 unleaded is fine for a stock engine and for our modified engines.

Suggested Mods (in order, first to last):

– Head setup (adds more power everywhere, especially bottom/mid)

– Rejet the carb/Slide mod (for 2017-2018)

– TSP ignition mod (adds more power everywhere, especially bottom/mid)

– Carb oval bore (2008-2016 models only)

– New V Force reed cage. These are slightly better in design than the stock reeds but power difference is only small.

– Cylinder porting (adds mid/top)

You can do all these mods at once or add one at a time.

Notes:

2017 models
The new 250/300 engine is very well designed and makes decent power, however there are some small issues with this engine that have a huge impact on how it runs. The biggest complaint we get is that low end power is very spluttery and weak and fuel economy is very bad. Its fairly common for stock bikes to get less than 60kms out of a tank. The 2 key areas that need addressing are the head (stock squish clearance is ridiculous, around 2mm), and the carb. Stock jetting is way off and none of the needles that are supplied in the spares kit are close to being correct.

We suggest setting up the head properly and rejetting the Mikuni as a minimum for this bike. This makes a huge difference to how the bike runs and dramatically improves low/mid power as well as fuel economy. Opening up the airbox will add extra hp up top but do this at your own risk as these bikes are still very prone to taking in dust. Our ignition mod is simple and cheap and adds a noticable amount of power from bottom to top with no risk to reliability.

Busting some 2017 KTM myths…
There is a HUGE amount of rubbish going around the net regarding the 2017 KTMs.  Unfortunately a lot of it is aimed at selling unnecessary products to uneducated riders so do yourself a favour and get some advice from someone who knows their stuff before buying some of these expensive “instant fix” products.
The stock reeds are absolutely fine, having a small air gap between the petal and the seat in still air has almost no bearing on what the petal will be doing when its opening and closing 100 times a second whilst covered in a film of oil. Dont replace the stock carbon fibre petals with the 1970’s tech fibreglass ones that are being sold on the net and advertised on youtube… they have a completely incorrect resonant frequency for this engine and are a big backwards step.
If you want to swap carbs on this bike then our suggestions is to consider fitting a short body Keihin PWK from an earlier model KTM125SX or a YZ250 (38mm). This makes a massive difference to part throttle running. There’s loads of accurate info about jetting these carbs to suit these bikes on the net and it will be a quick and easy install for most people. Fitting other aftermarket carbs that are marketed as “bolt on and forget” and “no need to adjust for temp/elevation” are usually not so straight forward in our experience… We have extensively dyno tested these carbs and have run them on our own bikes in the past. Take it from us… ALL carbs need proper setting up and constant adjustment for changing conditions, there is no way around this.
If you want the best value for money results then keep the stock reeds, setup the head and either jet the stock carb as best you can or fit a PWK. Anything else will simply cost you more.

Up to 2016 Models
For the SX models we strongly suggest setting up the head (especially on the 2014+ models), plus a carb oval bore and our standard porting (which includes mods the the powervalve). This combination gives nice gains throughout the rev range and up top without sacrificing reliability. Careful jetting and powervalve setup make a big difference. If you really want maximum mid-top power then advanced porting will give you bucket loads of arm pulling power!

For the EXC models we suggest setting up the head at a minimum (especially on the 2014+ models). We do a package of mods which is very popular and completely transforms the 250EXC engine… these mods include head setup, ignition mod and a carb oval bore. This is the best value setup you will find anywhere for this engine and makes it pull way harder from idle all the way to redline without sacrificing reliability.

Both EXC and SX model from 2014 onwards were given a different reedcage to previous years. We have seen some of these reedcages fail and suggest upgrading to a V Force reedcage if your reeds begin to show signs of chipping or fraying.

 

 

KTM250 2017

KTM300EXC (carb models):

Most popular setup 08-16 models:

The most popular setup for this model is head setup, carb oval bore, rejet carb and our ignition mod.  This setup gives more power everywhere, especially bottom/mid, better fuel economy and much smoother power delivery with no risk to reliability.

Most popular setup 17-on models:

The most popular setup for this model is head setup, carb slide mod, rejet carb and our ignition mod. This setup gives more power everywhere, especially bottom/mid, better fuel economy and much smoother power delivery with no risk to reliability. 

Jetting:
2008-2013: 35, NECJ clip 3, 165 main, AS1.75

2014-2016: 38, NECW clip 3, 168 main, AS1,75

2017-on: 27.5 or 30 pilot, 43-75 needle 2nd clip or 42-75 needle 3rd clip (1/2 clip richer overall), 430-450 main, AS1.5-2.5, TSP modified slide, float height 8.5mm. These specs work best with our head design… together they completely transform the bike. Slide mod is a must if you are going to keep the Mikuni carb. Otherwise swap to a 38mm Keihin (see SHOP).

NOTE: the 2018 bikes came with completely different carb specs (needles, emulsion tube, pilot jets, etc) to the 2017 models. In order to jet a 2017 model properly you will have to buy the genuine KTM updated 2018 jetting kit. We stock these and can supply one with your slide mod if necessary. We also include a couple of extra jets in the kit to make them suited to a wider range of conditions. 

These are ballpark specs only, for stock or lightly modified bikes. We do not accept any liability if you choose to run these specs.

Head:
Run a TSP head for more power everywhere over stock and less risk of detonation. See SHOP for prices and details. Our heads perform better and cost less than anything else on the market.

Carb:
2008 – 2016: Carb oval boring adds extra mid/top end performance. See SHOP for prices and details.

2017-: Stock carb size is fine.

Porting:
All years: Dont bother for trail riding. For racers we can get a lot more mid/top power with correct porting. See SHOP for prices and details.

Exhaust:
All years: Stock system is fine for trail riding and most forms of offroad racing. For more serious racers we suggest an HGS, DEP, or FMF. All of these add extra top end power. The stock silencer is absolutely fine for all levels of racing. If you want more power spend your money on head setup first and rejetting first… its much better value for money.

Ignition:
The stock ignition curve is a bit soft. Our ignition mod adds ignition advance across the board and gives more power everywhere (suitable for electric start models only).

Rebuild intervals:
Top end: Every 80 hours for trail riding. Every 60-70 hours for offroad racing.

Bottom end: Every 300-400 hours for trail riding. Around 200 hours for offroad racing

NOTE: it is very common to get dust through these engines even if you are careful with your filters. This can reduce engine life dramatically… we see lots of bikes with less than 50-100 hours needing full rebuilds.

Fuel/Oil:
Run 40:1 or 50:1. Normal 98 unleaded is fine for a stock engine and for our modified engines.

Suggested Mods (in order, first to last):

– Head setup (adds more power everywhere, especially bottom/mid)

– Rejet the carb + TSP slide mod

– TSP ignition mod (adds more power everywhere, especially bottom/mid)

– Carb oval bore (2008-2016 models only)

– New V Force reed cage. These are slightly better in design than the stock reeds but power difference is only small.

– Cylinder porting (adds mid/top)

You can do all these mods at once or add one at a time.

Notes:

2017-2018 models
The new 250/300 engine is very well designed and makes decent power, however there are some small issues with this engine that have a huge impact on how it runs. The biggest complaint we get is that low end power is very spluttery and weak and fuel economy is very bad. Its fairly common for stock bikes to get less than 60kms out of a tank. The 2 key areas that need addressing are the head (stock squish clearance is ridiculous, around 2mm), and the carb. Stock jetting is way off and none of the needles that are supplied in the spares kit are close to being correct.

We suggest setting up the head properly and rejetting the Mikuni as a minimum for this bike. We modify the stock #4 Mikuni slide to improve the part throttle response and we change to the 2018+ emulsion tube and needles. We also run a different spec for the float height and pilot jet. This makes a huge difference to how the bike runs and dramatically improves low/mid power as well as fuel economy. Overall our setup makes the Mikuni as good as it can be for part throttle riding and suits 80% of riders. If you really want the best possible jetting and most consistent runing all year round then fit a 38mm short body Keihin PWK carb. We sell these already jetted to suit your bike and the difference over the Mikuni is very noticable. The PWK makes a massive difference to part throttle running. There’s loads of accurate info about jetting these carbs to suit these bikes on the net and it will be a quick and easy install for most people as it works fine with the stock throttle cable. Fitting other aftermarket carbs that are marketed as “bolt on and forget” and “no need to adjust for temp/elevation” are aften not so straight forward in our experience… We have extensively dyno tested these carbs and have run them on our own bikes in the past. ALL carbs need proper setting up and constant adjustment for changing conditions, there is no way around this.
The stock reeds are absolutely fine, having a small air gap between the petal and the seat in still air has very little bearing on what the petal will be doing when its opening and closing 100 times a second whilst covered in a film of oil. If your stock reed petals chip or break then a take the opportunity to fit a V Force 4 reed cage. The main different between stock and the VF4 is the rubberised surface on the VF4 which helps to prolong petal life.

If you want the best value for money setup on the 17-18 carb models then keep the stock reeds, setup the head and either jet the stock carb or fit a PWK 38mm.

Up to 2016 Model
For the EXC models we suggest setting up the head at a minimum (especially on the 2014+ models). We do a package of mods which is very popular and completely transforms the 300EXC engine… these mods include head setup, ignition mod and a carb oval bore. This is the best value setup you will find anywhere for this engine and makes it pull way harder from idle all the way to redline without sacrificing reliability.

Both EXC and SX model from 2014 onwards were given a different reedcage to previous years. We have seen some of these reedcages fail and suggest upgrading to a V Force reedcage if your reeds begin to show signs of chipping or fraying.

 

 

ktm 300 tpi

 

 

 

 

 

 

 

KTM300EXC TPI 2018-on (fuel injected models):

Most popular setup 18-on TPI models:

The most popular setup for this model is to reflash the stock ECU with custom TSP maps and fit one of our billet 2 piece cylinder heads. We can also machine the stock 300 head to an improved profile if you dont want the billet head.
This setup gives more power everywhere, especially bottom/mid, better fuel economy and much smoother power delivery with no risk to reliability. Despite the extra power the bike becomes EASIER to ride and is much more predictable and tractable in tough condition. It helps to almost totally eliminate the part throttle splutter that the TPI bikes often suffer from, as well as the ‘pipe bang’ that they exhibit when closing the throttle at mid to high revs. This setup completely transforms the TPI and is by far the most cost effective setup on the market for solving the TPI issues. See our SHOP for info on the TPI Transformation package.

ECU: 

The stock ECU has very soft ignition maps and average fuel maps from the factory. The Sports Rider map is the best of the factory maps, but it is still very weak down low and the bikes are prone to spluttering at part throttle as well as experiencing a huge amount of ‘pipe bang’ on deceleration.

We have done a lot of work with the Athena GET ECU however were not totally satisfied with the results or price. As a result we have spent hundreds of hours developing our own methods of modifying the stock ECU to perform better than anything else on the market… the cost is much cheaper than the competitors products and the results are amazing.

Our ECU reflash service completely transforms the TPI bikes, giving them WAY more power at part throttle without being aggressive… instead they are smooth and predictable and will tractor up the gnarliest sections way better than a stock bike.

Head:
Run a TSP head along with our reflashed ECU for more power and smoother delivery throughout the rev range. See SHOP for prices and details. We can also machine the stock TPI head for similar results and less cost.

Spark Plug:
Fit an 8 heat range plug, especially if you do ANY mods to the engine. It will handle the heat better and has less chance of the porcelain braking apart than the stock 7 plug. This is particularly important if you are fitting an aftermarket head of any kind. We replace the stock plug with an NGK BPR8EIX which retails for approx $32 in Australia.

Porting:
These bikes make nearly 55rwhp with the right tune using the stock porting… so dont bother with cylinder porting unless you have a very specific application that requires maximum peak hp. Spend your money on head setup and ECU mods first.

Exhaust:
The stock system is excellent and makes great power for trail riding and offroad racing.  The stock silencer is absolutely fine for all levels of racing and aftermarket silencers show very small gains on the dyno. If you want more power spend your money on head setup first and ECU mods first… its WAY better value for money, and cant be dented or smashed 😉

Ignition:
The stock ignition curve is very soft. Our ECU mod adds ignition advance across the board and gives more power everywhere.

Rebuild intervals:
Top end: Every 80 hours for trail riding. Every 60-70 hours for offroad racing.

Bottom end: Every 300-400 hours for trail riding. Around 200 hours for offroad racing

NOTE: it is very common to get dust through these engines even if you are careful with your filters. This can reduce engine life dramatically… we see lots of bikes with less than 50-100 hours needing full rebuilds. A worn top end is also a common cause of running issues as it messes with the crank case pressure readings sent to the ECU. A frsech top end is a great place to start when trying to diagnose a poorly running TPI.

Fuel/Oil:
No need to add oil to the fuel, it is injected automatically by the ECU into the throttle body. Make sure the oil tank is topped up and always clean around the oil filler before adding oil… ANY dirt that gets into the oil tank can cause the oil pump to fail and destroy your engine!

Normal 98 unleaded is fine for a stock engine and for our modified engines.

Suggested Mods (in order, first to last):

– Head setup and ECU reflash

– Dont bother with anything else as the head and ECU package solves almost all of the TPI issues.

Notes on common TPI issues:

If you have a TPI that is spluttering badly, stalling or running erratically then do the following maintenance items first, as they cause a lot of TPI problems…

  • clean and tighten the earth strap where it bolts to the frame. A weak earth causes spluttering and running issues.
  • clean both ends of the ignition lead between the coil and plug cap… water gets in both ends and corrodes the ends of the lead causing a bad connection and weak spark… this leads to intermittent misfires and poor running.
  • replace the in-tank fuel filter and the in-line fuel filter often… they can leak or get blocked and cause a drop in fuel pressure… this causes lean running and is often a cause of part throttle issues and weak power.
  • If you’ve checked all of the above and still have issues then do a top end rebuild… it is EXTREMELY common for dust to get into these engines and wear out the top end. A worn top end causes blowby past the rings and weak power and also messes with the crank pressure readings sent to the ECU, which in turn causes the ECU to alter fuel levels, making the bike run even worse. Even if you have a low hour bike and swear that youve always done your air filters perfectly, look at doing a top end rebuild… its such a common story we hear from owners… “I always do my filters, cant possibly have dust in the engine” and then we open it up and see the very specific wear marks left by dust on the bore…