A new 2018 YZ250 build

cdoggy81
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1/1/2018
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St. Petersburg, FL US
cdoggy81 5/17/2021 9:37am
5/17/2021 9:37am Edited Date/Time 5/17/2021 9:37am
Matthias_26 wrote:
Long time since I've posted something... Put a new piston on the bike a few weeks ago, The OEM piston out of the parts kit had...
Long time since I've posted something...

Put a new piston on the bike a few weeks ago, The OEM piston out of the parts kit had 17 hours.
Bought a vertex size B and drilled 2 holes to lube the exhaust bridges.



At the same time also put a VHM head on with their stock insert(20.6cc)





Have rode the bike once now and can't really tell the difference between the stock milled head and the VHM head.
Compression was a bit lower with the VHM head measured with the previous piston.

Also have the new HGS silencer with the carbon end cap. The bike feels a bit snappier with this silencer but still has decent overrev.





Also my 2007 project bike is almost ready..








“Bought a vertex size B and drilled 2 holes to lube the exhaust bridges.”

Explain this one to me a little bit more if you could please. I’ve only seen them on 125’s with a true exhaust bridge in the center of the exhaust port but never on a 250 with a wide open exhaust port. I understand the concept but I did not think lubrication would be an issue there with these bikes. Did a particular builder recommend this or?

Thanks & nice work 👍🏻
Matthias_26 5/17/2021 9:50am
5/17/2021 9:50am
Matthias_26 wrote:
Long time since I've posted something... Put a new piston on the bike a few weeks ago, The OEM piston out of the parts kit had...
Long time since I've posted something...

Put a new piston on the bike a few weeks ago, The OEM piston out of the parts kit had 17 hours.
Bought a vertex size B and drilled 2 holes to lube the exhaust bridges.



At the same time also put a VHM head on with their stock insert(20.6cc)





Have rode the bike once now and can't really tell the difference between the stock milled head and the VHM head.
Compression was a bit lower with the VHM head measured with the previous piston.

Also have the new HGS silencer with the carbon end cap. The bike feels a bit snappier with this silencer but still has decent overrev.





Also my 2007 project bike is almost ready..








cdoggy81 wrote:
“Bought a vertex size B and drilled 2 holes to lube the exhaust bridges.” Explain this one to me a little bit more if you could...
“Bought a vertex size B and drilled 2 holes to lube the exhaust bridges.”

Explain this one to me a little bit more if you could please. I’ve only seen them on 125’s with a true exhaust bridge in the center of the exhaust port but never on a 250 with a wide open exhaust port. I understand the concept but I did not think lubrication would be an issue there with these bikes. Did a particular builder recommend this or?

Thanks & nice work 👍🏻
My previous YZ250 2007 was build by a tuner in the Netherlands, cylinder was ported, v force reeds and the intake were changed for more flow and the piston had 2 holes drilled like that.

Since then I keep drilling those holes, maybe it's not necessary but can't hurt I think...

this is the porting work, the cylinder is wasted now because the rod broke...






1
Matthias_26 5/24/2021 11:29am
5/24/2021 11:29am
chump6784 wrote:
Man that HGS silencer with carbon end cap is pretty. Kinda glad I sold my my yz or I'd have to buy one too
Haha! They also make the oval silencer with a carbon tip now







3
timobijnen84 5/25/2021 3:51am
5/25/2021 3:51am
To bad your 2007 was not finished a few months ago when i was looking for a YZ250.
It sold very fast which i understand with the good price and the current market.
1

The Shop

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timobijnen84 6/7/2021 1:39am
6/7/2021 1:39am
I saw you are selling a PPS exhaust. How did you like it?
I bought my yz250 with a PPS exhaust but it is very snappy with a lot of torque and no overrev. It already has vforce reeds and the squish is corrected.
Matthias_26 6/7/2021 3:38am
6/7/2021 3:38am
timobijnen84 wrote:
I saw you are selling a PPS exhaust. How did you like it? I bought my yz250 with a PPS exhaust but it is very snappy...
I saw you are selling a PPS exhaust. How did you like it?
I bought my yz250 with a PPS exhaust but it is very snappy with a lot of torque and no overrev. It already has vforce reeds and the squish is corrected.
I didn't ride with this PPS pipe. Came off rhe 2007 bike i sold a few weeks ago. I had a PPS in the past and tested it on the dyno last year also.

Less torque than DEP or HGS pipe but a lot of overrev. I didn't like the pipe that much because i had to use the clutch more out of the corners.

For me the bike is easier to ride with a DEP or HGS pipe
1
timobijnen84 6/7/2021 8:06am
6/7/2021 8:06am Edited Date/Time 6/7/2021 8:20am
I rode a friends yz250 which was tuned by grizzly racing and the power was super linear and the gears it would pull forever. My yz250 has les torque but when the powerband hits it lifts the front wheel and i need to shift very fast because it loses power up in the powerband. I will try a HGS pipe and longer silencer soon. I will also try to get a flywheel weight.
Matthias_26 6/7/2021 12:48pm
6/7/2021 12:48pm
timobijnen84 wrote:
I rode a friends yz250 which was tuned by grizzly racing and the power was super linear and the gears it would pull forever. My yz250...
I rode a friends yz250 which was tuned by grizzly racing and the power was super linear and the gears it would pull forever. My yz250 has les torque but when the powerband hits it lifts the front wheel and i need to shift very fast because it loses power up in the powerband. I will try a HGS pipe and longer silencer soon. I will also try to get a flywheel weight.
What pipe was on the bike of your friend? the HGS and DEP both have very lineair power and are easy to ride.

Also if the jetting is too rich you loose some overrev power.
I think you will like the HGS pipe better. the flywheel made my bike more predictable and easier to ride on hard tracks also. My bike lifted the front wheel a bit too much with the stock flywheel.
timobijnen84 6/7/2021 10:53pm
6/7/2021 10:53pm
He had a HGS exhaust.

My 125 didn't rev out and that was because it was too lean in the overrev. I will look at the plug and see if its to lean or rich.

I will also try a VHM head to see if it makes a difference with my modified head.

Pit Row

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