i have a 2006 450er and i bought an hrc kit and i was reading on this forums about it, i ride trails not really racing but i want to just add more power, i read that i have to change the pistons and rings after 15 hours? is this true if so i dont want to install it, i want something reliable not that i have to rebuild all the time, i need alot of info on this please let me know anything helps thanks..

 

I've never heard of this before, i wouldn't think you'd have to replace piston and rings after 15 hours; more like change the oil and filter and service ! I've owned a few honda motorcycle's and a 86' Honda TRX 350 Foreman 4WD, maybe if you build one for racing it might need rebuilding . But even then i think it would last more than 15 hour's ! Maybe you read something wrong honda's are good machine's................williebee

 

http://forums.atvconnection.com/mess...did/502109.cfm

 

I too didn't want the high mantiance of the HRC kit so I just replaced the stock air filter with a high flow type and removed the airbox lid and added a DMC exhaust along with replacing the stock main jet from a 120 to a 170 and replacing the stock non-adjustable needle with one from a CRF 450 putting it one the 3rd clip. It now has more pulling power and gets to top end faster than I'll ever need. If you dont put in the HRC kit atleast open it up on both ends. Try it you"ll like it!![img]i/expressions/face-icon-small-happy.gif[/img]

 

The 15 hour piston change is what Honda recommends on the '06. Whether you have the HRC kit or not, it's about piston wear and that comes from rpm and time. You can go longer but you just lose performance. If you wait too long, the piston will start wearing the cylinder and then you have to buy a new jug. I know of people that have 50+ hours actual engine running time on their pistons. I wouldn't go that far. I'll probably go 30 hours, then replace with a 14:1 piston anyway.

You own a high performance quad - not a tractor. It requires more money and maintenance to keep it running at its peak. When you replace the piston, get a CP piston and it will last longer. The OEM pistons have very short skirts and will rock in the bore much sooner than the aftermarket ones.

You know. This isn't any different than what is recommended for piston replacement onthe 250cc 2 -stroke MX bikes. Pistons need replacement on them frequently as well. It's the price we pay for making the power these things do. You can also plan on getting the valves done, new springs, etc after a while too. The other guys aren't immune from these maintenance items either, so don't think this is a Honda thing. It's a 450 thing...

Lastly, make sure you change the engine oil after every two rides and ONLY use oil with molybdenum in it (Honda HP4M or similar). Tranny oil can go every 4 - 6 rides. Don't use moly oils in the tranny or the clutch will slip.

 

Nowhere can I find where Honda recommends a piston change at 15 hours execpt on the HRC kit. Not in th eowners manual or the service manual,only HRC instructions. I've got more like 100 hrs and it runs like hour 1. I do change the oil less than 10 hrs and use HPM4 on the engine side. When it starts showing and sounding alittle different I'll open it up then. I dont run mine as hard as some of you guys.[img]i/expressions/face-icon-small-happy.gif[/img]

 

per racing conditons yea every 15 hours on the piston cause you wanna win right, i probably have 60 hours maybe on mine, and the hrc made it night and day diffrent, its a race quad and does not like to go slow, you really gotta use the clutch. the cam really livens it up, you get on it in an gear and the front end wants to come up its a blast. im glad i got the kit, awsome for dunes or trails. get it and you wont regret it. if you run a k and n get a uni filter or the outwear for it, they like to suck in stuff. hope this helps its worth the cash

cooper

 

Just to clear up a few things for you

The stock quad does not recommend a 15 hour piston change.

The recommendation of 15 hours in the HRC manual is 15 Racing hours, which it states clearly. First of all, Honda has to give a strict recommendation on changing out pistons for racing. For absolute optimum motor runnability they are recommending 15 hrs. This could include holding the bike up near redline for 15 hrs. If you look at is that way, it's not that bad. I drag alot when riding at the dunes and in a good weekend my bike is up not too far from redline about an hour out of a few hours of dragging and many hours of aggressive riding on a given weekend in reality (I would like to think it was more but not in actuality). For the average rider a 15 hr racing piston change will most likely mean they will put in a new piston and rings every couple years or so. For me it means that each winter I will freshen up my motor. If I didn't put a cam and hi comp piston in I would do it about every four years. Now that I have added about 10 horse to my quad I could never go back.

Also, keep the stock air filter in my opinion. There are a few dyno's online of the 06-07 trx450r that prove that these filters don't do anything for a bike like yours, except allow more dirt in (IMO) Keeping dirt out of your motor is the number one thing that keeps you motor happy.

 

ok well i bought the kit but i need to know if its a good idea to put it in. i dont do any racing just up and down the road, alot of wheelies and trail riding, where does it give it most of the power? is it a bad idea for the trails?

 

i guess the thing that makes me curios is the fourstroke was big on not having to replace pistons like a 2 stroke. and i am hearing that people are changing them continuoesly. but the price of a fourstroke top end is 3 times as much as a 2 stroke. i am kind of in the same boat with the hrc kit. i have the 06 450 to and i am wanting to install the hrc kit. but i went to this quad so i did not have to replace pistons once a month. so i am a little confused. i do not race anymore. so i am not as hard on my bikes as i used to be. but all of the feedback that i am hearing has me confused.