Posts
246
Joined
9/22/2017
Location
Summit Hill, PA
US
Edited Date/Time
2/7/2018 5:09am
What is the best way to adjust squish/piston height? These are the specs that came with the VHM head. My engine is getting a complete over haul this winter and I want to make sure everything is done as perfect as could be. When I was younger I just enjoyed riding my bikes and mostly kept them stock. Now at 28 I have almost as much fun working on them and trying different mods. Advice from the pros would be great.
If i'm right you get with vhm 3 different insert to choose and a fourth to make ur own.
A- higher compression for hardpack.
B- standard compression allrounder.
C- lower compression for the deep sand.
First of all what kinda tracks do u ride and what kinda power are u searching for. What kinda pipe are you riding with.
Example. I did ride with pro circuit and a base gasket of 1.2mm in sand. It gives no bottom power.
Now i ride with a 0.6 base gasket in sand.
Now i have a new handbuild pipe so now i'm gonna try to see how this works with the .6 gasket. If the power is enuff from the bottom. I can choose to get back to 49 sprocket of go to a 51 sprocket. Or i can lower the cylinder again or i can raise the cilinder.
So every one can say do this or do that but in the end you have to try to see how the bike rides like you want it.
Good luck.
The VHM head only came with one insert of my choosing. The way Langston power sports labeled them was (MX insert/SX insert stock or blind). I went with the SX for more bottom end. It’s nothing crazy but it’s higher than stock compression. I went with a slightly thinner base gasket but I didn’t want to make any big changes because I’m fairly new with making this kind of modification. I just want to know if I’m heading in the correct direction to get the desired specs that they suggest. I’m wasn’t sure if getting a thinner base gasket was the best wat. It my head the thinner the gasket the better chance of it failing.
Thanks.
If it's not enuff bottom then you can go the way what a lot of people did and that's milling the cylinder. But always wondering why people did that.
So in the end, you're the one what only can say and do what is the best for your self.
Good luck
It's also a heavier gauge
The Shop
So i thinks it a productionnumber or something like that. What else could it be.
I found a complete 07 engine for sale, it looked good and is “supposed” to be low hours and original. I bought it hoping it would be my fix all. I just got it today and I must say it’s perfect. There may be 2 scuff marks on it, the inside of the cylinder looks like a brand new off the show room floor( sorry just excited). Point being the cylinder on this new engine has these engravings and even a serial number. The cylinder that came on the bike doesn’t so it must have been replaced. I really can’t figure out what they did or what happened to this bike. I’ve seen a lot of things but this one got me. Anyway, a year and a lot of money later I finally have the bike I want. Brand new factory connection suspension, new redone motor with Lectron Carb/ VHM head/ Boysen rad valve.... I can’t wait to get this thing in the woods.
Yes, even the most won´t say it but as soon we see our bike we get excited. i´m one off those nutcrackers that talks to the bike lol
Enjoy the ride
P.S if anyone wants to buy a less than perfect CR250 engine, I’m your guy!!
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