Seized my Blur's engine!

[Lostmycage]

Well, with a 4.2mm crank, he's going to have almost 30mm clearance. Heh, sorry, couldn't resist.

The +4.2 crank is supposed to come with a 2mm shim, so if we ignore the other gaskets, there's a .1mm decrease in clearance over stock. He's also putting in a new head, so he'll probably double check just to be sure.

[davelhunter]

Babblefish,
I did not have the opportunity to see the work as it was being done since the work was done in Iowa. I shipped my motor to them since there was no one in my area that I could find that had experience with doing big bore kits on scooter motors. The company I send it to builds drag racing scooters. The name of the company is K & S Powersports in Indianola, Iowa. They are good people to work with & very knowledgeable. I think several members of the forum have spoken with them. If you give them a call they should have a record of everything they did to my Blur 150. I never had any problems with the motor and it ran great. I probably put around 500 miles on the motor and then I sold the bike.

[babblefish]

I LOVE IT! man this is great! keep the pics coming! I've definitely got my eye on this thread.

btw, what kind of vlave clearance are you going to get with that 4.2mm crank?

What Lostmycage said...
The compression ratio will probably be higher than stock. I just hope it's not so high that the starter motor can't turn the engine over. If it is, I'll have to decrease it by either removing material from the cylinder head dome or dishing the piston. A small increase in compression will actually be a good thing because it will give me a bit more power, though it means premium gas will be a neccessity.
The head was made to go with the big bore kit, but just in case I may check the clearance by using s lump of clay in the combustion chamber. This is done by putting some clay in the cylinder head dome, assembling the top end of the engine including valve train, manually turning the crankshaft through at least one complete rotation to cycle both the intake and exhaust valves, remove head then checking the thickness of the clay between the impression left by the valves and the imprint made by the piston.

[babblefish]

Babblefish,
I did not have the opportunity to see the work as it was being done since the work was done in Iowa. I shipped my motor to them since there was no one in my area that I could find that had experience with doing big bore kits on scooter motors. The company I send it to builds drag racing scooters. The name of the company is K & S Powersports in Indianola, Iowa. They are good people to work with & very knowledgeable. I think several members of the forum have spoken with them. If you give them a call they should have a record of everything they did to my Blur 150. I never had any problems with the motor and it ran great. I probably put around 500 miles on the motor and then I sold the bike.

Thanks for the info. I live in a scooter/motorcycle centric town so machine shops that can handle the job isn't a problem.
"The company I send it to builds drag racing scooters." - That explains their choice of an A9 cam then.
I'm not knocking their decision...if I lived where a driveway ramp is considered a hill...
Unfortunately, I live in a city where pitons, rope and camloks are required to accend some of the hills. Here, torque wins over absolute horsepower, in my opinion anyway.

[gearhead]

im interested to see if that 59mm cyl kit will fit. I thought the 58.5 was the largest it could go

[babblefish]

Just received my parts from ScrappyDogScooter. Not good news.

First, the 59mm big bore kit is nothing like what is on their EBay ad nor their website. It is not "Denso", it does not have the ceramic coated piston and the cylinder does not look anything like the picture. I can't tell where it's made although the quality looks good.

Second, the cylinder head. Their website states it is made in Taiwan, but the head I received is made in China and looks like it. Very rough/crude casting. Although port work has been done, it looks very amaturishly done and rough. The head doesn't look at all like the one I thought I paid for, in fact, it looks exactly like their stock 150cc head that they sell for $49.95.

You be the judge:

Picture of a stock 150cc head from their website ($49.95). Note the ribs next to the valve spring.


Picture of the head I received (paid $99.95). Note the ribs next to the valve springs. Also, look at the filled EGR hole.


Picture of the head I thought I had ordered ($99.95). If you look carefully, you'll see many differences from what I received. This is like one of those "look for the differences" puzzles.


I'm assuming there was a communication problem so I'll wait before I pass judgement on scrappydog. I've sent an email to them so we shall see how this will be resolved. Since this is their mistake, I hope they'll offer to pay the shipping back to them. So folks, don't order anything from www.scrappydogscooters.com until this is resolved. I'm really bummed.

[Lostmycage]

Those valve springs look used.

That's not cool at all.

[babblefish]

Well, if nothing else, Scrappydog does respond to email messages. But, it appears I'm getting the run around. They keep insisting that they sent the right big bore kit even though I sent them pictures of what I got, which is completely different from what their website and EBay ad shows. They also say that the head they sent was sent by accident and that it is their premium upgrade head that normally costs $149.95. I have the option of keeping it or trading it in for what I ordered. I really feel the head I ordered (made by Taiwanese Ruima) is of a higher quality. Since the mistake is theirs, I'm expecting they should pay for the return shipping cost, but we shall see...

[Lostmycage]

Have you measured the valves to see if they're actually bigger?

I'm guessing that putty (or is that wax?) is one of those premium additions...

[babblefish]

The valves are bigger: Intake = 30mm, Exhaust = 25mm

EDIT: Forgot to include the stock valve sizes:

Intake = 28mm
Exhaust = 23mm

That "filler" is some kind of epoxy glue. The hole goes directly into the exhaust port so the glue will see direct exhaust gas temperatures. I wonder how long it will last?

Lastest news on this saga: scrappydog told me the big bore kit I received is the "latest" version of the Denso kit. If you want my opinion, that's a load of...stuff.
Anyway, I'm done with this and have told them I want to return their "stuff" and get a refund. Unfortunately, their return policy says they only give store credit and that credit is only good for 30 days. What a load of...stuff. Good thing I paid with my credit card through PayPal. Hopefully that will give me some sort of buyer protection. Time to read-up on PayPal's buyer protection policy.

[charlie55]

You probably already know this, but there are lots of guys doing business under multiple names. In your case:

ScrappyDogScooters
1820 E. Desert Inn Road
2nd Floor
Las Vegas, NV 89169
Orders: (702) 689-9266 (Area code = Las Vegas)
Richard Main

-and-

China Moto Tech LLC
1820 E. Desert Inn Road
Suite 200
Las Vegas, NV 89169
Orders: (801) 448-5908 (Area code = Utah)
Dan Corrigan

Sorry about your getting bitten by these guys. Personally I think that offering "store credit" for misrepresented parts (and, importantly, unused parts in their original condition) is a crock since it leaves them free to f-up while your money is being held hostage. I can see a nominal restocking fee, but that's about it. Getting Paypal to piss on them a bit might give you some leverage. If your Paypal account is linked to a credit card, even better, they can both bust chops.

If you're looking for another source, you could try these guys in Canada.
They've got the whole kit (piston, camshaft, head, cylinder, vanilla frosting and sprinkles) for $219 USD, plus discrete parts as well. They also list specific model compatability, not just general manufacturer names. Here's a link if you're interested:


http://www.jiangwayne.com/scooter/p_tags.php?t=1&p=4

[babblefish]

Thanks for posting Charlie55. I didn't realize those two websites were the same, though I should have known since the pictures and text between them are exactly the same. I've run across that Canadian website before and probably should have ordered from them instead. But, it's too late now since scrappydog won't give me my money back. I've decided to compromise and keep the big bore kit since it looks to be well made and exchange the head for the one I originally ordered in the first place. Oh well, one never gets too old to learn something, eh?

[KS Power Nick]

OK I think I will give my $.02 in on the Blur engine.

There is plenty of meat left in the engine cases to punch it out to 63mm or like on Dave's engine 62mm plated cylinder. The PGO cases are well over built and VERY strong.

Second. Do not waste your money on an aftermarket cylinder head. Most "BIG PORT" heads have a major flaw in them that while they do flow better than a completely stock head for a descent performance increase. They do not compare to good ported stock PGO head. The ports on the aftermarket performance head are TOO big and hurt velocity. Also just pull out the intake port and stick your finger under the bottom side of the valve seat. You can feel it sticking out and that causes turbulance in the air flow. Hurting the over all performance.

Next. Any aftermarket crankshaft that I have seen while it will fit into the Blur engine cases. There is a problem when you go to install the variator. Because the blur uses a kickstarter that acts directly onto the crankshaft. It has LONGER splines on the end of the crank. If you go to install the variator with the stroker crank there will not be enough splines to install the kickstarter gear that goes on after the variator fan goes on.

[jrsjr]

Next. Any aftermarket crankshaft that I have seen while it will fit into the Blur engine cases. There is a problem when you go to install the variator. Because the blur uses a kickstarter that acts directly onto the crankshaft. It has LONGER splines on the end of the crank. If you go to install the variator with the stroker crank there will not be enough splines to install the kickstarter gear that goes on after the variator fan goes on.

[babblefish]

Thanks very much for your input KS Power Nick. I wish I knew about the spline issue before I bought my crankshaft. Well, I guess I'll have to wait until it gets here then figure out what I'm going to do.

The oversized port thing makes a lot of sense and I actually thought about that myself. That's one of the reasons I decided to return the big port head that was accidentally sent to me and exchange it for the head I originally wanted. I do plan to do some port work on this head, but just to improve flow a bit without going crazy with it.

I have a question for you or anyone else that has the answer: the outer diameter of the sleeve of the big bore cylinder is 60.3mm, while my stock cylinder is 62.4mm (the part that slides into the crankcase), in other words, it has a smaller diameter. This leaves about a 1mm gap between the sleeve and the crankcase opening - is this OK or is it going to be a problem? Seems to me it should be a tight fit to help prevent the sleeve from distorting/warping and to better support the piston through it's travel. I've built other aircooled engines before (motorcycle, VW, Porsche) and none of them have a gap. The vendor that I bought it from says this is normal, but I don't know...
He says that 125cc and 150cc crankcases are the same, but it seems to me that a 125cc crankcase would have a smaller hole for the cylinder - am I wrong? I'm so fed-up with dealing with this vendor so rather than argueing with him, I'll make a 1mm thick sleeve to take up the space if I have to.

[KS Power Nick]

What size bore did you end up going with? 59mm?? That 59mm is meant to fit into a standard gy6 engine case and you can tell the genuine stuff is different. If it were me. (because I have the tools to do it.) I would take the 59mm piston and punch out your stock cylinder. Since it has more meat to the sleeve compared to the aftermarket one.

[babblefish]

What size bore did you end up going with? 59mm?? That 59mm is meant to fit into a standard gy6 engine case and you can tell the genuine stuff is different. If it were me. (because I have the tools to do it.) I would take the 59mm piston and punch out your stock cylinder. Since it has more meat to the sleeve compared to the aftermarket one.

The bore is advertised as 59mm, but it measures 58.5mm.
Boring out the stock cylinder to 58.5mm is a good idea, but then that means I just paid $75 for a scooter piston...
The stock PGO cylinder is a very well made part with a thick sleeve. Seems like such a shame to not reuse it, but I think I'll just try and get a sleeve made for the new cylinder.

EDIT: While the piston diameter measures 58.5mm, the cylinder bore itself is 59mm.

[gearhead]

man, i hope you get everything worked out. pictures please

[babblefish]

Decided I'm going to make a sleeve to go over the cylinder's liner. I'll post a picture once it's done. Meanwhile, here's the big bore kit. It's actually very well made and the piston skirt is ceramic coated. The cast finish is very smooth and the machine work clean. The only bad thing is that the base gasket (green one) for the cylinder doesn't fit very well - the holes are off. Good thing the base gasket in the gasket kit I bought fits perfectly. For you sharp eyed arm-chair mechanics out there, yes the kit includes piston rings, I just forgot to put them in the picture.

[gearhead]

^that kit is from scrappy? isn't that one junk also?

[davelhunter]

I would highly recommend Nick and K&S Powersports if anyone here on the forum needs Blur performance parts, big bore kits, etc. The reason is that I sent him my entire Blur motor and he has experience & knowledge of exactly what works and what will fit since he built my entire custom motor that I had on my 150. It will probably save lots of headaches with all of these websites that sell "performance" kits that they say will fit all GY6 including the blur, which often times is not the case. Just my .02 I am in no way affiliated with K & S Powersports, I am just a happy customer:)

[babblefish]

^that kit is from scrappy? isn't that one junk also?

It's actually very well made as far as I can tell.
KS Power makes a pretty good point when he said that the PGO crankcase is very strong. Since I can't really afford to buy a new 220i right now, I'm thinking about punching it out to 62mm. So, with a 62mm bore and a 62mm stroke, I should end up with 187cc.

[gearhead]

you can actually run the 220 blur engine in your blur right now.... just run a bigger carburetor

[babblefish]

you can actually run the 220 blur engine in your blur right now.... just run a bigger carburetor

No.
1) Spare 220 engines in the US are probably as rare as hens teeth.
2) The price for a new 220 engine is probably around $2000.

[gearhead]

I've met and talked with one of the co-owners of genuine during amerivespa 2010. When i inquired about the 220 engine, they told me $1300

[KS Power Nick]

The 220 engine is not as easy to switch to carb as you would think. Everything!! except for a couple of small pieces are different between the 150 and the 220 engine. The intake manifold pattern is different. The exhaust botl pattern is different. Where the stator bolts to the engine is different.

It will bolt in place of the 150cc engine, but that is just about it.

[babblefish]

The 220 engine is not as easy to switch to carb as you would think. Everything!! except for a couple of small pieces are different between the 150 and the 220 engine. The intake manifold pattern is different. The exhaust botl pattern is different. Where the stator bolts to the engine is different.

It will bolt in place of the 150cc engine, but that is just about it.

Thanks again for your input Nick. As far as I'm concerned, all of the above issues are minor and can be worked around quite easily. I would assume that a stator assy. would be included with a new engine so integrating it into the existing harness should not be a problem. Of course, one would have to also buy the 220 voltage regulator in order to match the stator. But all of this is mute because I can't really afford to buy a 220 engine anyway.

While I have your ear ( ), how tight should the fit be between the cylinder sleeve/liner and the crankcase? I ask because I just noticed that even with the stock cylinder, there is a bit of play there.

[babblefish]

While waiting for my new head to arrive, I decided to do some port work on my old one just in case the new one didn't work out. Actually, I've got too much time on my hands...
Spent about three hours with the Dremel. Didn't go crazy and make the ports too big. Doing so could hurt street performance. In other words, it could reduce off-the-line torque.

Intake port is on the left, exhaust on the right.


Close-up of intake port.


Close-up of exhaust port. I'm not entirely satisfied with this. I may do some additional work on it.


After it was done, I noticed something interesting. Note the small hole to the right of the combustion chamber. This goes directly into the exhaust port and is for the exhaust gas recirculation (EGR).


Now look at the cylinders. Stock on the left, new big bore on the right. Yes, that's right, no EGR hole on the new one, but that's ok since I don't plan to use it. The problem is,
there's also nothing there to block-off the hole in the head - can we say "exhaust leak"? Guess I'll have to weld the hole shut if I'm going to use the old head...

[babblefish]

If the rebuilt engine runs well and gives me enough power, I may do a complete make-over and repaint it like the scoot on the far left. I like that burnt orangy-copper color.

[killbilly]

I like the orange...got that from a Canadian Blur site, right?

Also like a blue/white version I've seen around.

[babblefish]

Well, just received the Ruima cylinder head that I originally ordered from ScrappyDog. I think I've been spoiled by the quality of the PGO castings because the Ruima looks cheap by comparison. Not horrible mind you, but not as robust or refined as the stock head. It does have bigger ports and stiffer valve springs, but it does not have bigger valves as claimed by ScrappyDog. They're the same size as stock at 28/23mm. Not sure if I'm going to use it yet, but if I do, the ports will get a bit of Dremel treatment just to clean them up a bit and some combustion chamber massaging.

Also, KS Power Nick is completely right about the crankshaft splines - the splines on the +4.2 crankshaft are too short to engage the kick-starter coupler splines. However, the threaded portion on the end is long enough for the coupler plus the washer and nut. Other than that, it looks to be very well made. The main bearings are made in Japan and look to be more robust than the stock bearings. It's also a "full-circle" crank which should make it smoother at high rpms. So, we have two choices here - 1) use it as is and forgo the use of the kick-starter, or 2) find a way to mount the kick-starter coupler to the variator plate itself. I'm going to go with the second choice. Oh, and it came with a 2mm thick aluminum spacer and two base gaskets. One problem though - the spacer is not drilled for the oil supply port for the head. Easy enough to drill a hole, but if someone failed to notice that omission, things could get really ugly. Anyway, I'm going to let the vendor (autotech355) know of these issues because in his EBay auctions he states that it will work with PGO engines.
Pictures to come...

[KS Power Nick]

Now that you have that large of a crankshaft and have to use the cylinder shim. You will have to lenghten out your timing chain so it is not stupidly tight. Then your stock tensioner will not put enough tension on the chain and it will be too loose.

Those cranks are all sorts of fun to deal with. No fear I have the longer timing chains instock and also a manual timing chain tensioner that can be used with and crank and timing chain combination out there.

[babblefish]

Now that you have that large of a crankshaft and have to use the cylinder shim. You will have to lenghten out your timing chain so it is not stupidly tight. Then your stock tensioner will not put enough tension on the chain and it will be too loose.

Those cranks are all sorts of fun to deal with. No fear I have the longer timing chains instock and also a manual timing chain tensioner that can be used with and crank and timing chain combination out there.

Thanks for the info. So that extra 2mm is too much for the stock chain to handle? I would have thought the chain tensioner could handle the extra length by retracting it. When I disassembled the engine, the tensioner was extended at least 15mm.

PM sent.

[babblefish]

Just wanted to post an update. I'm still working on this rebuild, but my plans for the engine is going in another direction and I'm working out all the details right now. Basically, since I can't really afford to buy a new 220i, I'm going to take the engine as far as possible without sacrificing too much dependability (I hope!). But as many of you know, PGO's version of the GY6 engine is different in many little ways from a "standard" GY6 so there are a lot of little "niggles" that have to be sorted out. I'm learning a lot and having fun in the process!

Some "for examples" (subject to revision!):

"Standard" gasket sets are not. Most can be used in a PGO except for the transmission (variator cover), gearbox and exhaust gaskets.

The PGO 150 uses a bigger diameter exhaust gasket and it is resessed into the exhaust manifold rather than the head.

The crankshaft splines for the variator is longer on the PGO by about 5mm to accomodate the kickstarter coupler. The threaded portion of this end of the crankshaft is shorter than "standard" GY6 to make up for the longer splines. The overall length of the shaft is the same as "stardard" GY6. And no, one cannot simply weld the variator nut to the kickstart coupler and screw the whole mess together - the rotational force from the kickstarter is counterclockwise. In other words, in the direction to unscrew the nut.

The PGO has it's EGR valve mounted on the crankcase while the latest versions of "standard" GY6 have it on the valve cover. This means if you buy an aftermarket cylinder head, most likely your stock PGO valve cover won't work. You can bypass the EGR, but you still have to use a later style valve cover and block-off the EGR port in the head. Not all aftermarket heads have this port drilled out. Some are cast closed, but the EGR flange is still there and the valve cover mounting hole in that corner is in a different place.

If you buy an aftermarket big bore cylinder and intend to reuse your stock head, make sure you find a way to block off the EGR port in the head, otherwise, you'll end-up with an exhaust leak.

While not directly related to the engine, the Dr. Pulley variator and some of the other "high performance" variators have a bigger diameter variator plate (the side that holds the sliders/rollers) to act as an overdrive. Stock diameter = 112mm, Dr. Pulley = 115mm. This should give your scoot a higher top speed, but may require a longer belt to take advantage of this. I've ordered a longer belt (835 vs 812) to try it out.

The final outcome of all this will mean I will have a lot of new parts laying around that I can't use, so they will mostly likely go up for sale at a lost (on my part).

More to come...

[KS Power Nick]

Do not use the 835 belt. It will flap around and hit the cases. It is too loose. The only belt option is the stock one.

[Lostmycage]

Do not use the 835 belt. It will flap around and hit the cases. It is too loose. The only belt option is the stock one.

What he said!

[babblefish]

Duly noted guys, but you just know I gotta try. I'll be sure to post the shrapnel photos afterwards...

I'll probably not go the 63mm route because after machining out the crankcase bore, it will leave only 0.14mm wall thickness between the cylinder hole and the oil port hole. Two sheets of standard bond paper is thicker at 0.17mm (I measured it)!
Unless, unless I move the hole itself. Plug the original hole with an aluminum plug then re-drill the hole further out...hmm, might be doable.

[Lostmycage]

Sounds like you're talking yourself into some trouble.

I tried the 835mm belt and it flopped around in the case no matter what parts I tried and mixed and matched (NCY, Dr P & Prodigy).

The highest topspeed I got out of the Dr P variator and the Prodigy (Over range) driven pulley. The real trick to the Dr P variator kit is that the boss washer is about 2mm shorter which lets the pulley halves get closer and push the belt out further for higher gearing. I tried the PGO variator with the shortened boss washer and got just about the same top speed.

Just trying to save you a buck with experimenting with the transmission, as it sounds like you're already a few hundred into your engine. If you want to experiment with CVT bits, I've got all the stuff still sitting in a tray, including the 835 Gates belt (that I got from PS Nick). I've been meaning to sell the lot of em, but I've been lackadaisical about taking pictures.

[babblefish]

OK, I'll default to your experience.
Unfortunately, I already have the belt. Anyone want to buy a 835mm belt?

[gearhead]

pictures please

[Lostmycage]

OK, I'll default to your experience.
Unfortunately, I already have the belt. Anyone want to buy a 835mm belt?

Sell it on Scootdawg. The long case GY6 engines use the 835mm belt.

[babblefish]

Still working on gathering parts for my engine rebuild, but UPS is making it impossible to get my parts. I've had two parts shipments get sent back to the seller because I wasn't home to receive the packages. UPS used to give the option of picking-up a package at a local distribution center after three failed attempts at home delivery, but they no longer do that. After the third attempt, they immediately send the package back. Nice.
I've contacted the sellers to ask them to resend using an alternate shipper - USPS, FedX, Pony Express, a kid on a skateboard, anything but UPS.
It means paying shipping costs again but at this point, I don't care as long as I get my parts. UPS really sucks!!!

[Lostmycage]

That sucks, Babblefish!

I've had problems with UPS as well, but they were driver or area related. Not too many problems with them at my house, but I used to have a hell of a time getting packages at an apartment I used to live at.

[BlueMark]

It's impossible to get a package delivered to my home at a time when I will be there since I actually have a job. Fortunately I have no trouble having packages delivered to my work address.

[gearhead]

so you can run that 4.2mm stroker crank, you just have to delete the kick starter?

[babblefish]

so you can run that 4.2mm stroker crank, you just have to delete the kick starter?

Yes and no. The +4.2mm crank drops right in and everything bolts up to it except the kickstarter coupler. The easiest solution would be to just leave out the kickstarter coupler and fasten the nut directly to the variator. If a functional kickstarter is a must, then the second option is to drill 2 or 3 holes into the coupler and matching holes into the variator plate then pin them together using dowel pins. Do not use roll pins, they are not strong enough. The tricky part is drilling the holes into the coupler because it's hardened. It'll just laugh at normal drill bits. You also have to make sure the holes are equally spaced. Both issues are non-issues for me because I have access to a rotary table, a mill and carbide drills. A good machinist can do the job for a nominal cost. I haven't decided which route I'm going to go yet.
One other thing to watch out for is the final compression ratio. Depending on what cylinder and head combo you're using, the compression ratio may be too high. A stock Blur engine has a compression ratio of 9.4:1 or 11 kg/c. Not sure what this works out to in pounds per sq/in. A compression gauge will tell you if you're in the ballpark. If it is too high, material can be carefully removed from the combustion chamber to bring it down.
Lastly, you have to remember to use the 2mm aluminum spacer between the cylinder and the crankcase. I feel that just stacking regular base gaskets is not a good idea because there is a good chance that being soft, they can blow out over time.

[gearhead]

let us know how it is with the 4.2mm stroker crank. I want to do the same thing to my blur . Will the stock starter be able to handle all that compression?

[babblefish]

let us know how it is with the 4.2mm stroker crank. I want to do the same thing to my blur . Will the stock starter be able to handle all that compression?

Guess I'll find out...

[bluelghtning]

Just catching up on this. Sounds like you are having fun.

My blown Blur 150 is still sitting in my computer room. I get to look at it every day!

[gearhead]

what's the update on this babblefish?