Author Topic: New from the Netherlands with KX 85 Pitbike  (Read 6215 times)

0 Members and 1 Guest are viewing this topic.

Offline BFT-Mechanic

  • Newbie
  • *
  • Posts: 7
New from the Netherlands with KX 85 Pitbike
« on: January 02, 2016, 07:35:13 AM »
Hello to all of you,

I am a 47 jr old guy from the Netherlands with a 20jr old son who rides a pitbike.
We are member of a race team who ride just for fun, but are very competitive drivers.

At first our bike was a klx110 four stroker but didn't like the sound of it ( 2stroke rules  :-D)and had to many problems with the yx engine.
Last winter i completely rebuild the frame around a kx 85 engine.
The reason why i did not use the frame of the kx 85 motocross bike is because it is to large for indoor racing, in the winter we ride the pitbikes at the indoor kartcircuit were we live,
during the summer we ride outdoors in belgium and france.
I wanted it to be the size of the pit bike.
The handling of the bike is fantastic, a huge improvement compared to the four stroke frame.
And after one year with the kx engine i am very pleased with the engine switch.
I complete rebuild the engine including crankshaft en and had no problems with it for the whole year.
Also i have a spare kx 85 engine for tuning an testing.
This winter i am trying to get some more power out of the engine.

I would like to get in contact with other KX 85 riders to get some tips to improve the engine.

Here are some pictures of te project.




















« Last Edit: January 03, 2016, 05:40:44 AM by BFT-Mechanic »

Offline umberto

  • Administrator
  • Hero Member
  • *****
  • Posts: 2,488
  • First Ride 02-02-19
Re: New from the Netherlands with KX 85 Pitbike
« Reply #1 on: January 03, 2016, 06:15:50 AM »
That is some really nice work BFT-Mechanic!  I'll bet that little dude will really fly.  Do you have any video of it in action?
Perhaps I have a dirt bike addiction?

03 KX 250/88 KX 525/2017 KX250F - Goliath
17 KX250F/04 KX250
04 KX 250 - Lunchbox's Bike
05 KX 125/144

Offline Dutch-K5 Fan

  • Hero Member
  • *****
  • Posts: 759
Re: New from the Netherlands with KX 85 Pitbike
« Reply #2 on: January 03, 2016, 06:56:56 AM »
Welcome BFT. Fun bike you made.
Have you tried Rabbit Racing, and what kind of performance
Mods are you looking for?


Dutchie
Proud owner of a KX500AF

Offline BFT-Mechanic

  • Newbie
  • *
  • Posts: 7
Re: New from the Netherlands with KX 85 Pitbike
« Reply #3 on: January 03, 2016, 08:13:39 AM »
Thanks Umberto, little dude is flying  :-D lap times improved a lot last year.
I have a video but, i will do my best to get it posted.

Offline BFT-Mechanic

  • Newbie
  • *
  • Posts: 7
Re: New from the Netherlands with KX 85 Pitbike
« Reply #4 on: January 03, 2016, 08:21:14 AM »
Thanks  Dutch-K5 fan,

I will look into Rabbit Racing, maybe i find something there.
For the engine i am trying to gain some horsepower and revs.
I have no idea what the max output of a 85 engine is.
Before the pit bike we did some scootersprints, we had 25/26 hp out of a 70cc
I know this is a complete different engine.
At this moment i have 22.5 hp at 11300rpm.
The power is not that bad but the revs are in my opinion very low.

Offline BFT-Mechanic

  • Newbie
  • *
  • Posts: 7
Re: New from the Netherlands with KX 85 Pitbike
« Reply #5 on: January 04, 2016, 03:20:24 AM »
A video of Little dude
in action.

http://youtu.be/Z9IeQ-YMW3M

Offline umberto

  • Administrator
  • Hero Member
  • *****
  • Posts: 2,488
  • First Ride 02-02-19
Re: New from the Netherlands with KX 85 Pitbike
« Reply #6 on: January 04, 2016, 04:05:54 AM »
You're right, that dude will fly!  What size was that bike that was chasing you? 
Perhaps I have a dirt bike addiction?

03 KX 250/88 KX 525/2017 KX250F - Goliath
17 KX250F/04 KX250
04 KX 250 - Lunchbox's Bike
05 KX 125/144

Offline BFT-Mechanic

  • Newbie
  • *
  • Posts: 7
Re: New from the Netherlands with KX 85 Pitbike
« Reply #7 on: January 04, 2016, 04:54:25 AM »
The bike behind him is from the Yamaha R125 cup, all the bikes must stay the same to make the cup competitive.

Another video,

https://youtu.be/iX6tLDh0yMQ