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Manimal
02-15-2007, 06:27 AM
Never mind........I'm jus' a f00kin' idiot :toothless

I figured out what I need to do to assemble the kit within the MK spec.

Thanks all that clued my dumb a** in

eddiemcrider
02-15-2007, 07:13 AM
don't know mang.... :confused:

twinturba
02-15-2007, 08:27 AM
Sounds like a pierce customer support question!!

I think you could put two of the smaller together to go down from .20 but up from .08

Thats my .02:D

Pierce
02-15-2007, 08:59 AM
IM is a beautiful thing hu Manimal????? LOL Customer Support 24hr's or at least when i am on line.

Demoni
02-16-2007, 03:50 PM
Gotta love choices - just be happy they did not just pick one and toss it in the box for you.

I say run the thinnest base gasket or combo to increase the compression as much as possible wail still retaining clearance of the head. Only issue is port timing will be effected as well. Why they can't just give you 4 head gasket ?!?

But don't take my work for it.

Paz

Corey11c
02-16-2007, 08:19 PM
One general rule is that the thicker the base gasket you have, then the lower compression and higher port timing you get. Low compression and higher ports are aimed toward power at higher rpm. The opposite on the other end of the spectrum is true also. High compression and lower ports will give you more power lower in the RPM range.
Now what you have to determine is what rpm your pipe is tuned to. The shorter the expansion chamber, the faster the echo comes back into the cylinder which means that the pipe will work best at a higher rpm. The longer the expansion chamber, the longer it will take for the echo to get back into the cylinder which means that the pipe will want to make max power lower in the RPM range.
I would guess that the different base gasket thicknesses are to set your compression and port timing to match which pipe you have. If you are running a stock pipe it probably wants a thinner base gasket because the stock pipe isn't made to rev out really high.
An aftermarket race pipe will be shorter, therefore requiring higher port timing and lower compression.
That's the way I've always looked at it, feel free to correct me if I'm wrong.

Corey11c
02-16-2007, 08:22 PM
So if you want to get it perfect, dyno the bike with each base gasket and see which makes the best power curve for the pipe you have.
If you don't have a dyno....as if any of us has a dyno...then take it to stockton and run each base gasket and see which one you prefer.
If you don't feel like doing that, then just guess.

Corey11c
02-16-2007, 08:28 PM
ohh, yeah. If you are running the stock 50cc pipe on the 72 kit you will lose a LOT of HP due to the volume of the pipe being too small for the amount of air being echo'd back and forth. A 72cc pipe will have a larger diameter than the stock pipe. If you do have a 72cc aftermarket pipe, it is probably tuned for higher rpms, so I would go a little thicker on the base gasket, but not too thick try the .08 or maybe put the .08 with the .035.
I've heard that Carlos Neves will cut out thin sheets of paper to add shims to get the cylinder set in exactly the right spot.

Manimal
02-17-2007, 07:54 AM
Ryan,

Thanks for the 411........I never knew.

Manimal
02-22-2007, 08:09 AM
Update......

Ryan,

I was finally able to get an accurate squish reading of .042 in.

Keep in mind, MK spec is .8mm - .9 mm or .031 - .035 in.

With that, I am .007 in. over the upper spec. (.035), using a .020 base gasket.

Question..... will .007 really make a significant difference in performance vs being within?

I know, I know, I am getting too techinical. But being that I am fairly new to this stuff, I want to get the feedback to learn from.

*edited for correction*

Dangerous Dave
02-24-2007, 06:16 AM
Update......

Ryan,

I was finally able to get an accurate squish reading of .042 in.

Keep in mind, MK spec is .8mm - .9 mm or .031 - .035 in.

With that, I am .007 in. over the upper spec. (.035), using a .20 base gasket.

Question..... will .007 really make a significant difference in performance vs being within?

I know, I know, I am getting too techinical. But being that I am fairly new to this stuff, I want to get the feedback to learn from.

*edited for correction*



Not too technical at all, and yes, .007" is alot, aaaand you're .007" over the max, so that's worse. My kit also came with 4 base gaskets, and if memory serves me correctly, I ended up using the thinnest one which gave me a squish of .030". Yeah, it's a little tight, but no problems so far. If you combined the .007 and the .0035, you'd be right in spec on your squish. You're using their pipe as well, so I'd want to be in their spec if it was me. They did develop the whole kit afterall.
My $.02

Manimal
02-24-2007, 09:02 AM
Guys,

I updated my initial post, as my reading spec. posting was way off......yes, I'm f00kin' idiot!

Anycase, depending if I receive my shifter (shipped) by today, I will proceed breaking in the motor with my current .020 gasket tomorrow.

If it doesn't come today, then I plan to install and stack the .008 &
.0035 (=.0115) gaskets tomorrow....since I don't have any plans. The
.0115 in. gaskets will put me within the MK spec range. I just hope I don't have any leak issues having stacked gaskets.

Btw, I did a full warm-up cycle yesterday. Speaking of, what is the Derbi operating temp? fwiw, the bike warmed up to 133f. (based on my Daytona temp guage).

eddiemcrider
02-24-2007, 12:47 PM
C = F
50 = 122
56 = 133
60 = 140
70 = 158

My bike likes to operates between 60-70C, so you're in good company. When are we riding?

Dangerous Dave
02-25-2007, 07:18 AM
If it doesn't come today, then I plan to install and stack the .008 &
.0035 (=.0115) gaskets tomorrow....since I don't have any plans. The
.0115 in. gaskets will put me within the MK spec range.


Is there an echo in here?? :D Actually, the .008" and the .0035 will put you below spec. The .007" and .0035" will put you in spec.

Manimal
02-25-2007, 09:34 AM
Is there an echo in here?? :D Actually, the .008" and the .0035 will put you below spec. The .007" and .0035" will put you in spec.

You're right. Using the .008 will put me at .0365. I will use the
.007..........thanks! :)

Eddie,

We'll see. My bike is not fully operational, yet (missing shift lever :( ) also, tentative to weather.......

eddiemcrider
02-25-2007, 10:22 AM
You're right. Using the .008 will put me at .0365. I will use the
.007..........thanks! :)

Eddie,

We'll see. My bike is not fully operational, yet (missing shift lever :( ) also, tentative to weather.......

shift lever... did I miss something?

Manimal
02-25-2007, 12:53 PM
shift lever... did I miss something?

About 3 weekends ago, I went on a quick ride (ironically), which included a short run on an expressway. Well, within a 250 yard stretch of that, my shift lever vibrated off the bike. Apparently, I didn't torque down the screw enough to secure the lever. I combed high and low + 3 lanes of roadway, several times, and was unsuccesful in finding it :(

So, I sent Ray (in Florida) a shifter (I got with my motor) to have modified (shortened)......a must for a YSR/Derbi conversion.

eddiemcrider
02-26-2007, 10:13 PM
About 3 weekends ago, I went on a quick ride (ironically), which included a short run on an expressway. Well, within a 250 yard stretch of that, my shift lever vibrated off the bike. Apparently, I didn't torque down the screw enough to secure the lever. I combed high and low + 3 lanes of roadway, several times, and was unsuccesful in finding it :(

So, I sent Ray (in Florida) a shifter (I got with my motor) to have modified (shortened)......a must for a YSR/Derbi conversion.

DOH... did that with the kickstarter once.... just once. :D I found it though because I felt it hit my leg when it happend just didn't know at the time. I rode back and found it where it came off.

Just saw pics of the new lever. Sweet.

Dangerous Dave
02-27-2007, 11:58 AM
You're right. Using the .008 will put me at .0365. I will use the
.007..........thanks! :)



Your math still doesn't add up Bro. If you had .042" squish with a .020" base gasket, then using the .008" + .0035" will reduce your squish by .0115", which gives you a squish of .0305" (out of spec). Using the .007" + the .0035" will reduce squish by .0105, giving you a squish of .0315" (tight, but in spec). Using the .008" only will put you waaaay out of spec (MUCH too tight).
Make sense??

dankerson
02-27-2007, 05:56 PM
HAY MAN~ we couldn't get carlos to figure squish. howed you do it?
i wanna know

Dangerous Dave
02-27-2007, 07:51 PM
HAY MAN~ we couldn't get carlos to figure squish. howed you do it?
i wanna know


It's just addition and subtraction Bro. He said he had .042" squish with a .020" base gasket, and he gave the thicknesses of all the base gaskets he had to choose from. The math was easy. If you think that's cool, you should see me calculate tire sizes when people want to put big wheels on their cars without f**king up the speedometer. :D That takes me a couple extra seconds. ;)

Manimal
03-05-2007, 06:40 AM
Your math still doesn't add up Bro. If you had .042" squish with a .020" base gasket, then using the .008" + .0035" will reduce your squish by .0115", which gives you a squish of .0305" (out of spec). Using the .007" + the .0035" will reduce squish by .0105, giving you a squish of .0315" (tight, but in spec). Using the .008" only will put you waaaay out of spec (MUCH too tight).
Make sense??

Dave,

This is how I calculated my findings....

W/ .020 base gasket, my squish measured .042. Which put me over the upper suggested MK spec range of .035 by .007.

So, I added the .0035 + .008 base gaskets = .0115.
Subtract that from .020 = .0085 difference. Then I subtracted that number (the difference) from .042 squish measurement = .0335. Which then put me within the .032 - .035 suggested squish range.

And btw, thanks for your input. It is appreciated! If I am still wrong? well then, slap me upside my head and count it as a learning lesson :p (lol)

Marcus.....

How I measured squish? I used the solder wire method of measuring my squish. Being that I needed to get a reading anywhere from .035 or above, I chose a .05 dia piece of solder wire (soft).

I inserted the solder wire into the spark plug hole til' it hit and slide across the piston till it touched against the cylinder wall.
I then turned the rear wheel (while in gear) to allow the piston to turn-over a few times. The piston would then collapse/squash the solder wire where it maxes out within the cylinder. In my case, the gap or squish came out to .042 in.

Pierce
03-05-2007, 06:53 AM
All this math and no riding.....

Manimal
03-05-2007, 07:09 AM
All this math and no riding.....

:p

Go to the General Section to read my update ;)

ps, video footage coming soon :)

Pierce
03-05-2007, 07:10 AM
I saw good job!

Dangerous Dave
03-05-2007, 08:36 PM
Dave,

This is how I calculated my findings....

W/ .020 base gasket, my squish measured .042. Which put me over the upper suggested MK spec range of .035 by .007.

So, I added the .0035 + .008 base gaskets = .0115.
Subtract that from .020 = .0085 difference. Then I subtracted that number (the difference) from .042 squish measurement = .0335. Which then put me within the .032 - .035 suggested squish range.

And btw, thanks for your input. It is appreciated! If I am still wrong? well then, slap me upside my head and count it as a learning lesson :p (lol)



Au contraire, it is I who need slapped upside the head. That's what I get for trying to do simple math while home sick from work, then trying to make myself out to be a genius. It was the meds talkin'...that's my story and I'm stickin' to it. :o Obviously we've both figured out my error.

I watched your vid...that thing rips! Too bad my spare Derbi motor is one of the bastard 75s, 'cause I got waaaaay too many YSR chassis hangin' around the garage, but I don't think it's worth the trouble for that motor.

I saw in the video that you're running a GPR motor, rather than a Senda motor. Are all your internal ratios stock?? The final drive ratio I started out with was REALLY close to what you're running now, and it was so tall I could barely get away from a light, but once in motion I had all kinds of top speed.

Ok, here I go with the f**king math again. Don't worry, I'm using a gear ratio chart this time, so I don't have to do any actual math. :D

You said you're running 13/41 now, which works out to a 3.154 final drive. I started with a 14/44, which was a 3.143...pretty damn close. But like I said, it was hell to get away from a stop, and it would go faster in 5th than in 6th (couldn't pull top gear). I dropped one tooth in the front (I had a 13t laying around) which brought me to a 3.385...still too tall. I bought and installed a 12t, which brings me to 3.667!! And it's alot better, but still feels too tall to me. I'm getting about 76 -78 mph on top as-is, but I think I can do better once I get the gearing right. I'm waiting on my new MRD dash from Dan, which he tells me is gonna be here soon, then I'll actually have a working tach which I think will help alot. My "gut feeling" right now is that I need to go up either 1 or 2 teeth in the rear, but like I said, I think I'll wait until I have a working tach to make that call, since rear sprockets ain't cheap.

So now I'm really looking for YOUR input on this. From what I've read here, it doesn't sound like you've actually made a top speed run yet with yours. I'll be interested to know if yours will pull top gear with the ratios you're running now. Mine definately wouldn't. I'm running the SP 72 kit, SP pipe and crank, 24mm Mik flatslide and a modified stock airbox.

I'll be looking forward to your updates.

Pierce
03-05-2007, 08:43 PM
Actual Dave the motor is a Senda motor as you can see the kick starter in one of the shots.

Not sure why your set up doesn't pull you hard. I am running a 13-53 and mine just keeps pulling through all the gears till it tops out. I don't have a speedo but I am sure i am doing over 70.

Oh and your tach will be here soon. I know I know but I will get it to you right away.

Dangerous Dave
03-05-2007, 08:59 PM
Actual Dave the motor is a Senda motor as you can see the kick starter in one of the shots.

Not sure why your set up doesn't pull you hard. I am running a 13-53 and mine just keeps pulling through all the gears till it tops out. I don't have a speedo but I am sure i am doing over 70.

Oh and your tach will be here soon. I know I know but I will get it to you right away.


Hmm, I could have sworn I saw the block off plate where the kick starter goes. That blows that all to hell.

Your 13/53 is a 4.077 final drive! I'm far from that. Even if I go up 2 teeth in the rear, I'll still be under a 4.0 (12/46 is 3.833).

With my original gearing and this motor, I could pull 78 mph in 5th gear, but it would slow down when I shifted to 6th. Once I get my tach installed, it'll be alot easier to tell what the hell is going on down below. That's why I've been so anxious to get it. Yeah, it's still kinda cool here, but it's supposed to get up into the 50s Friday (after an overnight low in the 20s)! I just might have to brave the morning cold and ride the FJR to work Friday. Riding season is almost here...I can feel it. :)

Manimal
03-06-2007, 06:20 AM
Dave,

No worries, mate ;)

as for your calculated ratio's on final drive? all that stuff goes over my head and haven't the faintest idea of ever getting it right in theory. That being said, I rely on input from the bike and guesstimated what gear ratio to run :p

You knowing my gearing, what would you think the optimal ratio should be and or sprocket ratio?

Keep in mind, my front sprocket (13t), imo, is still a little tall, as you witnessed in the vid. And is why I plan to drop teeth in the rear, apposed to adding +1 up front.

Moreover, I am looking to just be within that sweet spot.......decent top-speed that allows me to climb hills without strain. Therefore, and tbh, I am not looking to set a top speed record. Quite honestly, it's useless for me being that I am restricted to urban roadways and or speeds. At most, 60 mph. Which so happens to be "flow" of traffic on local expressways, and without drawing too much un-wanted attention to myself :(

Btw, as Dan noted, I am using the Senda motor :D

Manimal
03-06-2007, 06:27 AM
Btw, why is the 75cc motor so bad?.....please explain

and lastly, why the stock air box with the 24mm carb, rather than a K&N or UNI air filter?

Pierce
03-06-2007, 06:31 AM
Btw, why is the 75cc motor so bad?.....please explain

and lastly, why the stock air box with the 24mm carb, rather than a K&N or UNI air filter?
Because your stuck with it forever, well unless you really want to put some money into the bike. It wasn't made for running fast it has a good amount of torque which is good but you are stuck with the stock set up as no one makes any type of cylinder upgrade for it.

Manimal
03-06-2007, 08:09 AM
ah......

But how is the power of the 75cc vs the MK 72cc, "SP" that is?

Moreover, will a 72cc PRO out hp the 75cc motor?

Imo, seems if the 75cc produces enough hp/torque, why would anyone want to upgrade?.....and keeping in mind, that the max for the 50 motor is a 72cc Pro kit.....or am I wrong......again? *cries laughing*

jus' curious is all.......

Pierce
03-06-2007, 08:21 AM
Well all the 72 kits make more power than the 75 standard. The 75 is a cast iron head with a dual ring piston. Longevity is there but high performance is not.

Manimal
03-06-2007, 09:25 AM
Well all the 72 kits make more power than the 75 standard. The 75 is a cast iron head with a dual ring piston. Longevity is there but high performance is not.

ah, now I see the light.......it's know wonder, then.

Thanks for clarifying ;)

patrickmotox
03-06-2007, 12:55 PM
also the stroker crank on a 72cc MK gives you 76cc at a whoopin
14.5K rpm. No way will the 75cc do that.....

patrickmotox
03-06-2007, 01:08 PM
also the stroker crank on a 72cc MK gives you 76cc at a whoopin
14.5K rpm. No way will the 75cc do that.....

eddiemcrider
03-06-2007, 04:42 PM
pierce what pipe was on your tard? how high did it rev? can't remember if we discussed this topic already.

Pierce
03-06-2007, 04:47 PM
I have the high PR/SP(comes with both end pieces). It rips big time.

Dangerous Dave
03-06-2007, 05:04 PM
You know, I went back and watched that video again...I must have a crappy monitor or something, 'cause I can't see the kick starter on that motor. The only clue I see is that the circle is black like a seal instead of the metal plug that goes there on a GPR motor.

As far as your final drive ratios, I can't be alot of help there, because I believe the GPR motor and the Senda motor use completely different internal ratios. I do seem to recall Ozzie saying something about the Senda ratios being much better for a race motor. I can tell you this though...you're planning to go in the wrong direction with your final drive. Really. I'm pretty much over being sick now, and haven't hit the crack pipe since at least last week, so I'm really sure this time. ;) If it bogs when you're trying to get away from a stop, then you either need to go more teeth in the rear, or less teeth in the front. A one tooth change in the front is typically equal to approximately three teeth in the rear. Front sprockets are cheap, and it sounds like you'll gladly trade top speed for off-the-line power, so I'd recommend you drop one tooth in the front and see how you like it. It should be a big improvement for you. Whether or not it's enough is to be seen. You can't go any smaller than a 12t front, or you'll chew the slipper off the swingarm, so if it's still too tall with a 12t front, then you'll have to go up teeth in the rear. Feel free to check me on this...lord knows I've screwed up before. :o

eddiemcrider
03-06-2007, 05:19 PM
Dave remember he is also pulling those gears on 12" wheels.

my SM with 15/52 (stock rear I think it's 52, and +1 up front) does 65mph on the flats at 11,500 rpm.

mk thrower, 72sp top end, prorace crank, 24mm oko carb, 17" wheel.... etc etc.

I think I am limited by my pipe as far as getting into the high RRRS.

Pierce
03-06-2007, 06:12 PM
I think I am limited by my pipe as far as getting into the high RRRS.

Oh yes you are. Just when you get really going it basically stops pulling right?

eddiemcrider
03-06-2007, 06:14 PM
Oh yes you are. Just when you get really going it basically stops pulling right?
:p yup .... will hit you up on a pipe... or if you run into a used one ;)

Dangerous Dave
03-06-2007, 06:23 PM
Btw, why is the 75cc motor so bad?.....please explain

and lastly, why the stock air box with the 24mm carb, rather than a K&N or UNI air filter?


As Dan already stated, there's just NOTHING you can do with the stock 75 motor. I spent an obscene amount of money a couple years ago trying to make it fast...and it was...for about 500 miles at a time, then it would grenade itself. Go through it again. 500 miles later...KABOOM! It would do over 80 while it was running, but the pistons would self destruct. Not like detonation, they would literally break from the high compression and high revs. After towing it home 4 times in one season, I declared the project a failure and went back to a stock 75 motor while I shopped for a 50 to build an SP motor out of. The stock motor is very low compression, low revving, very reliable, just not real fast.

As for the modified airbox, unless you're looking to build a monster race motor (that you don't mind rebuilding often), a well designed airbox will make more power than a pod type filter (Uni, K&N, MK, etc). The dyno will bare that out. Now I realize that the stock airbox isn't exactly designed for high flow, but you can fix that.

Here's the thing; We all know that if you pull off the side of the road in your car, and open your door just as a semi is passing by, you're gonna get the door sucked right out of your hand by the vacuum created by the passing semi. Air can create a vacuum as it passes by too. Imagine the turbulence around your K&N sticking out in the middle of your bike as you're haulin ass down the road. Vacuum is really the absence of pressure. Your intake charge flows into the motor because the pressure inside is lower than the pressure outside. Anything you can do to create more pressure outside will improve your volumetric efficiency (the cylinder's ability to fill itself). That's why everybody and their mother is using ram-air now. The more mixture you stuff in, the more power you get out. An engine will make more power drawing air from a still pocket than from a turbulent one. So if air is rushing PAST your K&N, you're creating a low pressure area right where you don't want one.

The filter element inside your airbox is big. It has at least as much surface area as a pod filter. The restrictions are the inlet and outlet. I modified the inlet by removing the little rubber inlet spigot. Then I cut the plastic across the top next to the inlet hole and used a heat gun to soften the plastic and flex it up like little air scoops. On the carb side of the airbox, I removed the rubber tube and made the hole bigger. Then I cut a short piece of PVC pipe (about 2" diameter) and shoe-gooed it into the airbox at the appropriate angle, with it sticking into the airbox a little bit, like a velocity stack. I used a rubber boot and two clamps to attach it to the Mikuni 24mm flatslide, which is installed into a Honda CR80 intake manifold and bolted up to a modified reed cage (it's got a wing in the middle...that's another story). If you're running a stock intake manifold, you're cheating yourself badly, because that thing is a pea-shooter.

Maybe I'll try to get some pics of all this stuff this weekend. I learned all this stuff from a couple of guys who used to do alot of flow-bench testing on race motors for F&S Kawasaki/Harley Davidson (I was a mechanic there a couple decades ago). F&S has been a major player in flattrack and motocross for decades. The owner isn't afraid to spend money to get on the podium. That's also where I learned NOT to over-carburate.

I do still have a spare stock 75 motor, just in case something happens to my SP motor, so I can still ride the GPR. I shudder to think how much money I've spent on that bike in the 4+ years I've owned it, but I just love it. Even when I still had my R1, I rode the Derbi more often. I still ride it more than my FJR1300. It's my ride of choice. :)

Manimal
03-07-2007, 08:09 AM
Dangerous Dave,

Here is a pic of my Senda motor......

Dangerous Dave
03-07-2007, 04:31 PM
Dangerous Dave,

Here is a pic of my Senda motor......


Ahhh, now I can see the kick-starter shaft sticking out. How did you plug the hole from the injection pump? I'm used to seeing a block off plate there. Did you plug the hole from the inside?

Pierce
03-07-2007, 04:35 PM
Yeah how did you do that? I used a mountian bike bar end from the handle bars along with a piece of plastic to hold it in place. Not the prettiest but works alot better than the carbon fiber one TCR sells.

Manimal
03-07-2007, 04:53 PM
What y'all be talkin' bout? :p

As weird as it seems, per MY motor, it looks like something was supposed to be mounted, only externally. As you can see, there is nothing internal exposed. Moreover, it has not been plugged, neither. Looks completely factory.........cues twilight zone music Unless, the factory forgot to drill it out for the injection pump (LOL)

And is why you see no block off plate......nothing to leak out :p

Funny you guys bring that up, Ray from Florida, asked the same question (lol)

Pierce
03-07-2007, 04:55 PM
No oil comes running out of that hole? Your motor does have oil on that side of the engine right? Can you stick your fingure in there and touch the water pump above or the clutch plates??

Manimal
03-07-2007, 05:04 PM
No oil comes running out of that hole? Your motor does have oil on that side of the engine right? Can you stick your fingure in there and touch the water pump above or the clutch plates??

Nope......nada

Trust me. There are only molded counter bores that exist, along with the threaded mounting holes for an injection pump. that's it! Again, there is nothing internal exposed, let alone for any liquid substance to pour out.......otherwise, my motor would have destructed itself during my first ride after installing the motor (last year, to be exact).

Again, cues up twilight music (LOL).

If you want, I can take a closer pic of that area.....

Dangerous Dave
03-07-2007, 06:18 PM
Nope......nada

Trust me. There are only molded counter bores that exist, along with the threaded mounting holes for an injection pump. that's it! Again, there is nothing internal exposed, let alone for any liquid substance to pour out.......otherwise, my motor would have destructed itself during my first ride after installing the motor (last year, to be exact).

Again, cues up twilight music (LOL).

If you want, I can take a closer pic of that area.....


So you're saying none of the three holes go all the way through the aluminum??? Dude....that's too bizzarre. Have you had the clutch cover off the motor? Does it look like someone welded up the holes on the inside? Derbi didn't make that motor without oil injection, did they? Anybody? Freakin' weird man. :confused:

Manimal
03-08-2007, 06:03 AM
Upon installing the motor, and seeing that there was no block off plate, I thought to myself that was one more thing I would have had to purchase/add. But, after inspecting the area, and seeing that nothing internal was exposed, I was relieved (one less item to purchase) and really, thought nothing of it.

And no, no JB weld or silicone or anything that is visable or obvious use of a "plugging" method was used to seal the area Again, looks totally factory.

cues up the song.....How Bizarre, How Bizarre

Btw, I must add, that this motor came from an ex-race bike....bought from a private seller So, its' very possible that the owner found a way of capping off the area, and made it look/seem to be "factory" done.

flaysr50
04-04-2007, 03:58 PM
Hey where did you get the specs on the squish band? I was told by Ozzie to just use yamabond and seal the base gasket. The bike works well but i did get a leak in the front. I'm going to try the .004 or .008 base w/ the spray tach gasket coating and see how it works. Ray

Pierce
04-04-2007, 04:21 PM
Hey Ray, I have never used any type of sealer on the base gaskets and never had a leak. I also only used one gasket so I have pretty high compression.

Manimal
04-05-2007, 05:00 AM
Ray,

The spec sheet came with the 72 kit I got from Pierce.

Btw, what are some remedies of a do-it-yourself leak tests?

........is one of them; while the motor is running spray a mix of dish soap/water around the base of the cylinder?

flaysr50
04-07-2007, 06:53 AM
I wasnt using any gasket, just the yamabond. Daren, if you have a leak, you'd know. Black sauce oozes out and gets all over the motor and flys on the fairing.

can you email me a copy of that squish band paperwork?

Manimal
04-09-2007, 07:46 AM
can do....I will need to scan it.

Altho', it just generally says squish should be between .8mm & .9mm (.031 and .035), that's it.

btw, this is for the SP 72cc kit, not sure if the Pro kit is any different

Manimal
04-09-2007, 07:47 AM
can do....I will need to scan it.

Altho', it just generally says squish should be between .8mm & .9mm (.031 and .035), that's it.

btw, this is for the SP 72cc kit, not sure if the Pro kit is any different