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396 Posts
Discussion Starter #1
Hello everyone, it's been a long time since i have been on the forums. I have been playing with my 65 Chev Malibu SS and i have had a blast the last 2 years. I built a motor for it that runs great. Did some autocross stuff and entered the Street Machine Challenge 2 years in a row. Didnt win **** but had a total blast. Good to be back here as some exciting things are happening or have happened over the last year. First and foremost. I crashed my 2007 Stratoliner S this last spring. Totaled it out. I came out of it pretty much unscathed other than i really screwed up the tips of my 2 index fingers. they will never be the same. In paying homage to my old bike i would like to mention I drove it for 8 years and put on 70,000 miles. it didn't burn a drop of oil and was a total power beast and i miss it greatly. One good thing that came from the crash was i bought a 2010 Stratoliner Deluxe with the insurance money. It was a demo bike and has ALL the Yamaha accessories. Stuff i didnt even know they made. The bad thing is, it's a California bike. OMG this thing is pitiful power-wise compared to my 07 Strat S. My 07 would rip this Cali bike to shreds. My old bike never knocked, pinged, fizzed, farted or did any weird stuff. this Cali bike does all the above, gets horrible mileage and has no power. Cali pollution stuff is a joke. Anyway this has prompted me to move forward with having some hot rod parts made for this wonderfully successful motorcycle engine. I am working with "Those Dyno Guys" in Zimmerman Minnesota to port the heads, bore out the throttle bodies, make custom cams and anything else that will be needed to make more power. Matt has dyno'ed about a dozen Strats/Raiders and they are all about the same power including the 120 CID bikes that came thru his shop. They (120 CID) didnt make nearly the power that was expected. The bike basically can't breath and runs out of power on the high end. So since this lack of power is driving me nuts I decided to work with Matt to see what we can do for power and make this power available to everyone as a kit. My Deluxe will be the test mule.
So I have sent my ECU off to Ivan for the reflash. I will need to raise the RPM limit because of the cams
Bought a PCV with auto-tune module
Bought cam cores
Bought a set of heads
All of these parts sourced thru ebay so far.
I still need to buy a set of throttle bodies.
Still plan on using the stock air box and the B.A.M. - it looks like it should work at this point.
Matt is talking about making custom exhaust as well. The rear cylinder takes a hard turn and he want's to fix that and improve the flow.
This is working out great for me. Matt is going to do all the work and i just need to pay for hard parts. Matts pay off will be selling the power kits. This kit will work for the Raiders as well. I am hoping to have this running by spring. We still need to drop my bike off at Matts shop so we can degree the cams. The service manual will tell you valve lift but no cam lobe duration or cam lobe centerline specs are given. Thats all top secret yamaha stuff. The cams will be drive-able but should deliver a big increase over stock. key goal is to keep the rpm range within Ivans set RPM limit of 5850. That should not be a problem. The stock cams start to peter out at 4750 RPM. Matt looked at the heads ports and said Yamaha left a lot of power on the table. He had a serious gleem in his eye. Matt can pull some serious power out of the harley's and he has gotten somewhat bored dealing with the same HD stuff, day after day. This Stratoliner engine is a new ball game for him and he is eager to make some serious power. You can see the gears turning in his head. I'm excited. To bad we didn't do this a long time ago. At least this engine is still alive in the new venture. I am hoping Yamaha is going to release a whole bunch of bikes based on the new venture platform. if they dont they will miss the buss once again. There are a lot of HD guys that dont want a gold-wing style of bike. they want something like the strat deluxe. Not a BMW/Goldwing type of bike. anyway, i'm getting off an a tangent.
I hope to have hot rod parts for liners/Raiders by spring. Stuff that actually makes some serious power. Cams that work. Heads that flow. an engine that makes some serious power and performance without blowing up.
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396 Posts
Discussion Starter #3
Stratoliner/Raider Cams

Finally got the stock cam info
Well it's been a long cold winter in Minnesota but i finally got out and tore my bike a part and degreed the cams. It was miserable but right now i'm pretty damn excited. I'm going to share the cam info and explain some of the cam timing events so your not in the dark with the stock stuff.
So here is the stock magic.

Intake Duration is 214.50 degrees.
Exhaust Duration is 217.00 degrees.
Installed Intake Centerline is 98.25 degrees ATDC.
Installed Exhaust Centerline is 107.50 degrees BTDC.
LSA is 102.9 degrees
Overlap is 10.00 degrees.

So what does this all mean?
Well first the intake lobe center line is advanced.
The general rule is;

Advancing cam lobe centerline
Builds More Low-End Torque
Decrease Piston-Intake Valve Clearance
Increase Piston-Exhaust Valve Clearance

Retarding Cam lobe centerline
Builds More High-RPM Power
Increase Piston-Intake Valve Clearance
Decrease Piston-Exhaust Valve Clearance

So as expected this engine builds max torque down low and typically runs out of steam early.
The duration is more than I expected it to be. I was thinking 190ish. Larger motors do tame the cam profiles so maybe I should have expected this.

4 valve heads suffer from exhaust gas reversion due to really good low lift flow. That's why the cams only have 10 deg of overlap.The trick is for me to keep the overlap low to keep reversion at a minimum and pick a new intake & exhaust lobe centerline geared to higher RPM and then determine a LCA (lobe Centerline Angle) that will increase duration.
I am still working on these numbers as I just got in the house from degreeing the cam.
Now, I called Web Cams and they have a grind for the start cams. They basicly increased the duration and left the lobe centerlines as stock. There are a few problems with this approach and i'm not going to pick it a part.
The important thing was the cost It was $840.00 or $880.00 bucks, a lot of friggin money. I would like to do something similar the Brains Airbox Mod. I got 10 people to trust me and split the total cost for the first 10 kits. This got me in the door with the water jet company and those 10, first run people, got their BAMs for cost. I would like to do the same with cams. If i can get some people together and trust my cam spec's i would try to get 10 - 20 sets welded and ground up.
FYI, I still need to call web cams to see if i can get a price break based on quantity. It will also be a week or two before I come up with my cam spec's.
I tend to get a little radical and i'm not going to make some pussy cams that friggin piss me off. I'm also smart enough to realize iI can't go full tilt as i still like to drive across country. I have my cam cores that i bought off ebay for $150.00 bucks. So i'm ready to go for it. If you guys want to move forward your going to need to find some cam cores. They can be straight out of your bike if you wish to go that route. Buy new cams from yamaha or search ebay like i did. I chose to buy cam cores so i can still ride my bike and/or put the stock cams back in if i'm not happy with the Brain Cams. That's my plan.
Anyway, it's supper time and i'm going to go eat and dream about my Stratoliner Deluxe tonight. If your interested in going for cams the easiest way for me to keep track is if you contact me thru my website.
Here is the link.

396 Posts
Discussion Starter #4 (Edited)
Cams made, installed and failure points.

Well I got my custom cams installed. I have not posted to this for such a long time for a reason.
I can break it down like this.
Got cams made at web cams.
Once cams were ready to ship Web cams would not ship them to me.
They said the lifters will fail. They are supposed to have a ceramic base and the supplier is now a lame duck - long story in itself.
PR racing has lifters being made by lame duck but lame duck can't keep up with demand.
TBrain tried to get lifters from PR racing but they won't do that. Got to buy their cams as well.
PR racing doesn't have any lifters, at that time anyways.
TBrain is a process engineer and deals with all kind of different engineering stuff , including PVD coatings which are ceramic in nature but really thin.
I researched and found special cower cam saver lifter, took it a part and had a special TBrain PVD coating applied to the lifter body.
TBrain told Web cams to ship those cams i got bad ass lifters.
TBrain installed cams in his Strat D
Strat D gains 6 - 7 HP gross BUT if you look there are areas in the curve where i am 10 - 12 hp more than before and it is all at higher RPM. Bike idles smooth and runs very strong.
Took it to the drag strip and ran 12.77 @ 100.xx mph. My Strat D is heavy. It was a Yamaha demo bike and has EVERY single bit of Aftermarket Yamaha parts that Yamaha made for these bikes.
I ran it 11 times in a row. 9 passes were all 100 mph, not 99, not 101 but 100 mph.
I could not control the urge to rev the **** out of it and drop the clutch. This causes the bike to launch like a sling shot and then momentarily bog, then go like a raped ape. I could have cut 1/2 sec by slipping the clutch like a normal take off.
i have about 4000 miles on the cam and lifters and so far it sounds O.K.
I might take it a part this winter and inspect the cams and lifters for wear.
Thats were im at.
as dyno tested
Ivans ECU reflash
PCV with auto tune module
Stock air box with Brains Airbox Mod
K&N air filter
stock 2:1 exhaust with Roadhouse muffler
EXUP was unhooked.
Still using stock length push rods with new cams.
Auto decompression still works.


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6,851 Posts
very impressive

Its great to hear from someone modifying their engine who knows what he is doing.

I see so many wannaBees on craigslist who tore into a good bike, had no idea what they were doing, and now they are dumping the bike in pieces because they cant get it to run right.
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