loss of bottom end

[redpowerhrc450r]

i have a 04 trx450r with the hrc kit and a full yoshimura pipe. it feels like it has a loss of bottom end but a really hard pulling top end. i can pull sand mnt in third half way and then when i kick it into second it starts to pull really hard. any one got anything to help me out on this?

[d3ktrix]

Has it always been like this? Or was something changed?
Did it start when the HRC kit was installed? Or did it always have the kit?

The 05 HRC cam has a pretty lame bottom end, it's all about the top end.

[warr72]

I ran a full yoshi on my 08 and it moved the power all to the top end. Tried rejetting but the combo of the pipe with my other mods did not work together.

[redpowerhrc450r]

Originally posted by d3ktrix
Has it always been like this? Or was something changed?
Did it start when the HRC kit was installed? Or did it always have the kit?

The 05 HRC cam has a pretty lame bottom end, it's all about the top end.

well i just bought the bike. The guy i bougth it from said it lagged kinda bad after the exhaust put on. but he said the stock exhaust he held third all the way up the hill. but it runs so good right now i dont want to put the stock exhaust back on and mess with the jetting and have it messed up. is there any other way i could keep my full pipe on and get my bottom end back. I was just going to do a je 12:1 compression piston. or change my gearing cause its at a 15/39 i was going to try a 14/39.

[d3ktrix]

15/39 is pretty tall gearing for only a cam/exhaust. What size tires? Sounds like it could be over geared, especially for hills.
You should like 14/39 a lot more.

I'd say thats the problem before the engine. Thats like desert racing gearing :P

[redpowerhrc450r]

Originally posted by d3ktrix
15/39 is pretty tall gearing for only a cam/exhaust. What size tires? Sounds like it could be over geared, especially for hills.
You should like 14/39 a lot more.

I'd say thats the problem before the engine. Thats like desert racing gearing :P

ya im going to try that cause its hauls a** on the flats but hills it just dogs a little.

[WilRideAnything]

I agree the gearing is to tall. The motor can't pull it in the lower RPMs. Put on a 14t and you should be fine.

[Black R/T]

13/39, itll fix ANY bottom end issues you have.

[warr72]

Wish I would have been more patient. Called the guy I sold my pipe to and he loves it. Asked him about the gearing and his front sprocket is smaller. Oh well live and learn the expensive way...... :ermm:

[redpowerhrc450r]

Originally posted by d3ktrix
15/39 is pretty tall gearing for only a cam/exhaust. What size tires? Sounds like it could be over geared, especially for hills.
You should like 14/39 a lot more.

I'd say thats the problem before the engine. Thats like desert racing gearing :P

i just pulled my front sproket off and it is a 13. i counted wrong. what should i do? idk what to do

[d3ktrix]

What is ur jetting?

Jetting might be way off, or needs a valve adjustment, or timing is off.

If its none of those, then I would say the HRC cam just isn't for you.