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I know it is an old thread, but I'm also thinking about changing the stock air intake setup to something smaller, plus I don't like the plastic velocity stacks as they not sturdy as metal parts. My question is that do I need to re-tune the bike after a change or not? I'm looking for a cosmetic change only, not a performance, so I rather not go along with mess anything.

Regards,
Mihaly
 

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I know it is an old thread, but I'm also thinking about changing the stock air intake setup to something smaller, plus I don't like the plastic velocity stacks as they not sturdy as metal parts. My question is that do I need to re-tune the bike after a change or not? I'm looking for a cosmetic change only, not a performance, so I rather not go along with mess anything.

Regards,
Mihaly
Most likely a retune is required, depending on how much you change. Depends on what you expect for how it runs. Some are perfectly happy with a bike that runs like shit. LOL. Basically, you will know if tuning is needed or not , for what you want out of it.
Ron
 

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Most likely a retune is required, depending on how much you change. Depends on what you expect for how it runs. Some are perfectly happy with a bike that runs like shit. LOL. Basically, you will know if tuning is needed or not , for what you want out of it.
Ron
Currently all stock on the bike, I like the way she runs, and prefer to keep it that way, so this is the baseline.. :) So if I add that smaller intake with better airflow you say there is a chance that I need to get someone to re-tune the bike (I will check how to do that just to see)?
Mihaly
 

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Currently all stock on the bike, I like the way she runs, and prefer to keep it that way, so this is the baseline.. :) So if I add that smaller intake with better airflow you say there is a chance that I need to get someone to re-tune the bike (I will check how to do that just to see)?
Mihaly
See how it runs and go from there. It will let you know if it needs some tuning. Not sure how a smaller intake setup will give better airflow? What are you planning to use?
Ron
 

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See how it runs and go from there. It will let you know if it needs some tuning. Not sure how a smaller intake setup will give better airflow? What are you planning to use?
Ron
I would use the tabperformance (or moto hooligan) super intake system mentioned above. Shorter intake would increase airflow imo as air needs to travel less to get into the engine. You know very long straw vs no straw.. :)
Mihaly
 

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I would use the tabperformance (or moto hooligan) super intake system mentioned above. Shorter intake would increase airflow imo as air needs to travel less to get into the engine. You know very long straw vs no straw.. :)
Mihaly
There really is no restriction to the stock velocity stacks , so the straw is plenty big enough as is. The bottle neck is below the throttle bodies. Most times these claims of more hp are a result of the accompanying tuning. Same would happen if you tuned your stock bike.
So in the end, your going for more of a cosmetic effect then anything else.
Ron
 

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Another thing, how much the air temperature difference inside with this setup compared to the original? Just curious as the cold air is more dense and better for the engine, but with this intake the air comes below, from the hot engine.

Mihaly
 

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Another thing, how much the air temperature difference inside with this setup compared to the original? Just curious as the cold air is more dense and better for the engine, but with this intake the air comes below, from the hot engine.

Mihaly
Only time that hot air is a problem is on shut downs where heat will rise up an soak the IAT. Going down the road the air is pretty much ambient. I've found the stock box location not great for two reasons. It's up high where most of the heat goes when shut down and being high it takes forever for the IAT to cool down going down the road since the inlet air from the fork area vents somewhat miss the top of the box. The sensor is in a dead air zone where neither intake air or external air from the vents cool it quick enough back to ambient or near ambient. The temp that the engine is actually seeing in the intakes. A heat soaked IAT will lean the mixture, most noticeable after the hot engine has sit for 10+ minutes and restarted. Coolant temp could be 140F and the IAT 120F as an example on a heat soak restart situation. There can be a brief window where it comes off of the calibration warmup table and O2 sensors come online to try and correct the afr, which can be 15-1 - 17-1. Symptom is a hunting, loping idle in that transition. No O2 sensors, it will remain until the IAT cools back from bike moving down the road. Different IAT locations generally produce different temp readings, which is one reason a tune should be done, and done at the stable norm temp of that sensor and at a normal coolant temp.
Ron
 

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Only time that hot air is a problem is on shut downs where heat will rise up an soak the IAT. Going down the road the air is pretty much ambient. I've found the stock box location not great for two reasons. It's up high where most of the heat goes when shut down and being high it takes forever for the IAT to cool down going down the road since the inlet air from the fork area vents somewhat miss the top of the box. The sensor is in a dead air zone where neither intake air or external air from the vents cool it quick enough back to ambient or near ambient. The temp that the engine is actually seeing in the intakes. A heat soaked IAT will lean the mixture, most noticeable after the hot engine has sit for 10+ minutes and restarted. Coolant temp could be 140F and the IAT 120F as an example on a heat soak restart situation. There can be a brief window where it comes off of the calibration warmup table and O2 sensors come online to try and correct the afr, which can be 15-1 - 17-1. Symptom is a hunting, loping idle in that transition. No O2 sensors, it will remain until the IAT cools back from bike moving down the road. Different IAT locations generally produce different temp readings, which is one reason a tune should be done, and done at the stable norm temp of that sensor and at a normal coolant temp.
Ron
Cheers, that is a great overview on what are the possible effects. I saw your modified air filter solution, where is the IAT on that? Also if you could share the process/picture how you did it I might consider modifying mine.. :)
Mihaly
 

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Cheers, that is a great overview on what are the possible effects. I saw your modified air filter solution, where is the IAT on that? Also if you could share the process/picture how you did it I might consider modifying mine.. :)
Mihaly
Probe tip sits between pleats of the filter element. Basically a piece of plastic made to plug the IAT into and bolted to the bottom section of air box. Stock location and here both end up the same temp eventually but here, it doesn't heat soak to as high of a temp down lower and cools a hell of a lot faster when moving down the road. Typically stock and this location, stabilized temp is about +5F of ambient. Heat soak effect is about 4-5% less in leaning the afr when the engine is restarted after sitting for 10-20 minutes. This is mostly due to a lower mounting where there is less heat rise and temp. The higher you mount it , the more the effect of heat soak to the sensor.
Ron
 

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