Part of the rear brake improvements we are using on Sean's bike is a KX450F rear brake caliper that has been slotted and a heat sink will be added to help keep it usable for him... Yes, Sean is very hard on rear brakes :lol:
I like the idea, but it seems like the best spot to add surface area would be directly behind the piston bore? I've forgotten the name but there is also a coating process that is specifically designed to improve thermal radiation of whatever it's applied to that might net you a bit more cooling as well.
Your attention to detail is fabulous. Not many shops/builders show the care and aptitude you demonstrate.
I can also appreciate you showing the bad results along with the good results.
I'm going to eventually plate my 2006 Crf250r with a '89 CR500 motor in it. These 500 2 strokes are a dying breed and the ability to street ride them is just too cool.
I've only rode a few times so far. Sand Lake was a blast. Although the low speed manuervering had a bit of a learnign curve! I was going down a hill I had just climbed up no problem and doing just 5mph, which was the cause, the front end sunk and I went over the bars! lol It was a fun trip though. I think of it like a boat.. when planing the turning is easy and you can carve while giving it gas. When you want to slow down for something more technical, that was my issue.
I've been blasting logging roads. So far I've been to the top of 4th... probably 60mph or so. These 500's are something else. I can appreciate both brands!
How do you like your front sand tire? Does it help with low speed turns?
I'm just up in Portland so if I need some work done or any parts, I'll be sure to get in touch.
This is the engine that won last years National Two Stroke Championship at Glen Helen.
It was built by Frenchy and the bike was piloted By Sean Collier.
We are building Sean a whole new bike right now.
But in the mean time I was asked to fix the shifting issues on this engine and make it survive for another few races with little to no money.
Easy to ask... Hard to do.
In the end I think we nailed it but I won't know for sure until this weekend when Sean rides it at the Vet Nationals at Glen Helen.
I'll let you know the results :anim_peep:
Jason thinks that each engine he builds is one of his kids..
Sometimes he gets a bit carried away :lol:
What we did to this engine to freshen it up was not what we wanted to do.
It was all we were allowed to do.
I saw a lot of room for improvement but that was just the point.
They didn't want any improvements other then longevity and better shifting.
I will get more into that later..
But here is the list:
Disassemble, clean, and carefully inspect EVERYTHING.
Vapor blast all the aluminum, and polish everything that could be polished.
Replaced all the shift components with used but in spec parts.
All were hand polished.
Replaced the clutch plates.
Hand ground the dogs on the trans gears.
Replaced the piston and Ring set with a very low hour set from my own bike.
Every bearing, seal, and gasket, was replaced.
Hand filed the clutch basket ears and the clutch hub, then polished them.
The left engine case was replaced as the existing one was junk.
Hand lapped the cases, cylinder, and head.
It really could have used a plate job but we just didn't have the time or the money to do it.
Also, some of the gears were pretty poor but I think after Jason tuned them up they should be ok for a while.
So, it wasn't what we would have liked to do but it should survive until we get Sean's new bike built.
Feel free to ask.
WPC Treatments for your motorcycle.
What is WPC Treatments?
Basically it is Micro shot peening surface metals.
Steel, Aluminum, bronze, even Nikasil plating can be treated.
So I went on Youtube and watched the two demonstrations done by Izumi, the owner of WPC Treatments.
Ok, looks promising but how does those demonstrations translate into motorcycle parts?
Most of us know that shot peening makes the surface metal harder... But peening needle bearings and bushings? I admit I was a bit skeptical. So I had some parts WPC treated and decided to do a very garage like test to see if there was any noticeable differences between treated and untreated.
Here is the set up..
Like I said, it's a very garage like test...
But the results were very close to one another.
1st test. I ran this set up with the WPC treated bushing and bearing. The trans shaft and the clutch basket were untreated.
2nd test. I ran this set up with a brand new untreated bushing and bearing... Same trans shaft and basket.
3rd test. I ran this set up with a used bearing and bushing... Same trans shaft and basket.
4th test. Because some will complain about my unscientific method of testing I ran the WPC treated parts again with a worn battery and duplicated my initial results.
I ran each test 5 times.
I tossed out the high number and the low number (They were very close) then averaged the three middle numbers.
The WPC Treated part ran for an average of 36.19 seconds.
Now you have to guess how long the untreated new bearing and collar ran for :thumbup:
Sorry guys... I've been busy and forgot about it...
The WPC treated was the clear winner...
The WPC Treated part ran for an average of 36.2 seconds.
The worn bearing and collar ran for an average of 20.3 seconds.
The brand new Factory bearing and collar ran for an average of 10.6 seconds.
So, there is a few things to learn here.
1. The WPC treatment works and works well.
My personal bikes will not get built without this treatment.
So yes, I give this process a 10/10 rating.... You NEED this..
2. Loose is fast as my buddy Adam Millar always says.
He is right.
I guess that is why a engine is the fastest right before it blows