Possible problems: rocket key

6560 Views 28 Replies 5 Participants Last post by JARYphoto, Feb 24, 2013

JARYphoto

Discussion Starter · Feb 12, 2013

Hello guys.

I just received my rocket key and proceeded to install. I noticed that the rocket key is smaller in overall size than the stock one. It fits in the key notch on the crank but not snugly. Width is the same but length and depth are shorter. It's way to easy to instal and uninstall whilst the sock key is kind of press fitted, like I have to press it nicely so it sits flush on the crank.

Is this normal? Is this the correct key?

I ordered from PBP. The description said: "Timing Advance Key/Rocket Key - 49cc Pocket Bike 33cc, 36cc, 43cc, and 49cc"
http://www.pocketbikeparts.com/Timing_Advance_Key_Rocket_Key_p/x7tm301664.htm

Some pics...

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JARYphoto

Discussion Starter · #2 · Feb 12, 2013

One more pic of the rocket key installed on the crank. Check the empty space left in the notch in front of the key. As installed, the key does not have any side play on the notch. it also fits snugly and seems secure (as stated, no side-to-side movement) although the stock key fits very tightly. Should this be normal?

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fabian7777

· #3 · Feb 13, 2013

It looks like you have a piston ported engine. The "rocket key" you had installed before is actually a woodruff key which is only used for cag engines i believe. Im pretty sure the rocket key you have now is the correct size. I remember when installing mine that it was smaller length wise than the notch.

CAM2

· #4 · Feb 13, 2013

The rocket key is good but that chewed-up crankseal is bad.........................

JARYphoto

Discussion Starter · #5 · Feb 13, 2013

Thanks Fabian!!! Yes I did forget to mention it was a piston ported engine.
Well, I did some measuring and it all seemed to be ok. I just placed the key as far as possible in the crank notch and installed the flywheel. Installed everything back and turned the engine. I had to crank it as many times as I would normally do and fired as usual. Noticed that the carb would have to be retuned at low speeds so I did. As soon as it warmed up I made fine adjustment to the idle and began to rev it slowly. All seemed normal and engine responded nicely. So gave it some real gas and it felt more responsive. Adjusted the high speed needle bit by bit until I got the max rpm's my exhaust permits (stock scooter muffler). **** does it feels nice now. Initial revving from idle is way better and high revs are well sustained for the 5 to 7 seconds I kept it at WOT. Seems to rev cleaner, though I know it can get way better with a higher performance exhaust (without having to go for heavier internal mods).

The v-stack seems to do its job as I had to richen the mix do to the increased air flow. Looks real nice and sporty. A filter is a must!!!

So, for all the newbies like me trying to give some muscle to these little engines in a budget, this is the way to go. For less than $20 (+ sh) the gains are very noticeable and engine performance is enhanced nicely. Couple this to a better performing exhaust and I bet it will suffice most recreational riders, without the need to extensively mod the internals of your engines.

Some pics.

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JARYphoto

Discussion Starter · #6 · Feb 13, 2013 (Edited)

CAM2 said:
The rocket key is good but that chewed-up crankseal is bad.........................

Hey cam2. The seal is not chewed up. As a matter of fact, when I fist got this engine, I just cleaned it up and started it. Since all seemed well, I let it cool down and then dismantled it. Checked the bearings, seems, piston rings, sleeve lining, everything, and it was all good. Seals were rubbery and soft and before installing the crank, I lubed the inner contact area with some water resistant automotive green grease. Worked like a charm. So what you see is a bit of grease left from when the crank spindle passed through. Trust me, I have good automotive experience and if I had seen bad seals, they would have been replaced.

Btw, thanks for the carb tuning video. Found the link on a thread about someone having trouble tuning his carb. Real easy to follow and my engine's performance was drastically enhanced when I tuned it before and after these simple mods.

Now, I have to order a new pull starter or a new pawl. Pull starter's not engaging and could be that the small plastic shoe on the pawl broke off or the starter wheel broke. It still winds but just doesn't engages the pawl. Wanted to make a vid of the running engine but can't freakin start it now!!! I'll see tomorrow.

Hey Cam, I have a ?. I read your rocket key thread and noticed that the pic you used to explain the key position on a piston ported engine, the crank has a female flywheel thread for a bolt, as opposed to mine that has male thread for a 14mm nut. What crank is that, a fcc or a stock one?

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CAM2

· #7 · Feb 13, 2013

JARYphoto said:
Hey cam2. The seal is not chewed up. As a matter of fact, when I fist got this engine, I just cleaned it up and started it. Since all seemed well, I let it cool down and then dismantled it. Checked the bearings, seems, piston rings, sleeve lining, everything, and it was all good. Seals were rubbery and soft and before installing the crank, I lubed the inner contact area with some water resistant automotive green grease. Worked like a charm. So what you see is a bit of grease left from when the crank spindle passed through. Trust me, I have good automotive experience and if I had seen bad seals, they would have been replaced.

Btw, thanks for the carb tuning video. Found the link on a thread about someone having trouble tuning his carb. Real easy to follow and my engine's performance was drastically enhanced when I tuned it before and after these simple mods.

Now, I have to order a new pull starter or a new pawl. Pull starter's not engaging and could be that the small plastic shoe on the pawl broke off or the starter wheel broke. It still winds but just doesn't engages the pawl. Wanted to make a vid of the running engine but can't freakin start it now!!! I'll see tomorrow.

Hey Cam, I have a ?. I read your rocket key thread and noticed that the pic you used to explain the key position on a piston ported engine, the crank has a female flywheel thread for a bolt, as opposed to mine that has male thread for a 14mm nut. What crank is that, a fcc or a stock one?

Oh thats good news then..the pic made it look like it was bad........

You may have the pawl lever in the wrong hole......The GSMoon pull and pawl are the best....

The crank with rocket key on the piston ported engine in the rocket key thread is indeed a full circle crank......

EPR

· #8 · Feb 13, 2013

I would round all the sharp edges on that V-stack.

JARYphoto

Discussion Starter · #9 · Feb 13, 2013

Thanks cam2 and epr.

I'll check the GSMoon pull and pawl. Should they fit without any mayor modifications? I eliminated the electric start stuff and tried to use the long bolt but it bent on the second pull. So I just eliminated everything and took the pawl and drilled the threads off and inserted a small peace of metal tube inside the hole and used a 10mm bolt to secure the pawl to the crank. It had been working good until now. Seemed as if installing the rocket key increased engine compression (which I feel totally stupid saying it cause it's impossible). So after running the engine for a while and shutting it off and trying to restart it, the pull system gave away. Gonna open it up now to check what really happened.

EPR... I will definitely smooth out the sharp edge. Didn't like that at all when I first saw the pic on the PBP store. First gotta get my dremeling tools together.

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JARYphoto

Discussion Starter · #10 · Feb 13, 2013

Ok, so I know now what the GSMoon starter assembly is and I'm ready to order, but have a couple of ?.

How does the GSMoon pawl mounts on the crank? The stock one that I have (rectangular shape with rounded short sides and plastic lever) threaded onto a bolt and the bolt into the crank. I eliminated this and drilled the threads off and fitted the pawl to the crank with a 10mm bolt. Does the GSMoon pawl needs a special bolt or something to center on the crank?

Also, should Is there a better spark plug to buy that would burn better?

Tnx guys.

CAM2

· #11 · Feb 13, 2013

NGK BPMR7A sparkplug..gapped to .030"

This is the GS Moon pullstarter,,,Its alot tougher than pullstarting the engine on a single plastic tab..Its got two stainless steel rods that turn the disc in two places

It bolts on just like the rectangular one..........

http://www.ebay.com/itm/Mini-Pocket...DefaultDomain_100&hash=item43988fab14&vxp=mtr

JARYphoto

Discussion Starter · #12 · Feb 13, 2013 (Edited)

Thanks Cam2.
PBP has a better price on them including shipping. Plus the 10% off coupon code (3030110) is a $2.30 savings. All adds up to around $24 shipped.

JARYphoto

Discussion Starter · #13 · Feb 21, 2013

Got the GSMoon pull starter and installed it. Nice setup, feels like it engages very positively. Did the same mod as before on the stock aluminum pawl in order to install it. Worked nicely.

On the trike, had to raise it up. It now sits at 6-3/4" from the floor so should be very secure to commute in it as opposed to when it was very low, though I really liked the low look.

Some pics and vids...

Low style (before):

Raised (after):

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JARYphoto

Discussion Starter · #14 · Feb 21, 2013

Vids:

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MathieuOuellette

· #15 · Feb 21, 2013

looking good!! I was looking into this for myself to put on my mini quad, but I think it would work better with this... deflate the rear tires and get snug fitting pvc pipe over them, then reinflate so they dont move. you've got a gas powered drift trike. Drift triking is hot in new zealand right now, but they dont have motorized trikes they get pulled by a car with a strap or go down hills. with that thing you could be the local drift king haha.

JARYphoto

Discussion Starter · #16 · Feb 21, 2013 (Edited)

Hahaha, the local drift king!!! Lol!!! Well, my idea is derived from a drift trike. I'm not saying it my original idea cause I saw a motorized drift trike on the web. A very low one, which was what I loved about it, but the frame was very different from mine. Not as strong and well built and the rear of the frame was completely square.

Yes, the hobby is getting to the states and here in Puerto Rico too. I want to get some PVC pipe and slap it on my wheels but for now I will leave it as is until I have a well running trike. After that, let the good times slide!!!

Edit:
I've seen some mini quads with kart wheels on them. Don't know how they modded the spindles and rear drive axle but they sure looked awesome.

MathieuOuellette

· #17 · Feb 21, 2013

Haha definitely!!! I'm rebuilding my quad motor right now for maximum power and reliability, and will definitely getting some drift wheels ready for the spring.. Also looking into a track and ski conversion, but I have all summer to worry about that for next winter... Right now I'm focusing on getting this thing to run pristine.

CAM2

· #18 · Feb 21, 2013 (Edited)

JARYphoto said:
Hahaha, the local drift king!!! Lol!!! Well, my idea is derived from a drift trike. I'm not saying it my original idea cause I saw a motorized drift trike on the web. A very low one, which was what I loved about it, but the frame was very different from mine. Not as strong and well built and the rear of the frame was completely square.

Yes, the hobby is getting to the states and here in Puerto Rico too. I want to get some PVC pipe and slap it on my wheels but for now I will leave it as is until I have a well running trike. After that, let the good times slide!!!

Edit:
I've seen some mini quads with kart wheels on them. Don't know how they modded the spindles and rear drive axle but they sure looked awesome.

Benefield paid bigtime by adding a real kart axle w/bearings and kart hubs that clamp onto the axle to bolt the rear tires to........It paid off in sweet looks and most likely awesome handling.........

Depending on if your axle is splined or not determines whether you can buy different hubs that work for the kart rims...........

JARYphoto

Discussion Starter · #19 · Feb 22, 2013 (Edited)

Your right Cam2. Kart rims would be ideal. The thing to look for when adding kart rims is the hubs. They come in a variety of sizes grouped in two main types of metric systems and determined by the axle diameter. They are either metric sized hubs or SAE hubs. Metric hubs are measured in millimeters and vary from 25mm up to 50mm (maybe more but these are the norm). SAE hubs are measured in inches and the most common are 1" and 1-1/4".

Wheels too come in two main different options, metric and American patterns. They use mostly three screws to mount on the hub. Metric pattern is usually a three hole on a 58mm circle and the center hole on the wheel where the axles goes through is 40mm in diameter. American pattern has three bolt holes on a 2-1/2" circle and center diameter of 1-1/4 (I think, can't remember well on the center hole).

I made an error and bought metric pattern wheels but had 1" (SAE) aluminum axle. Since hubs come either American or metric, not combined, I thought I was f'd up. But searching the web led me to bmikarts . com. They have hubs that adapt SAE axles with metric pattern wheels. Awesome product!!!

So when you're up to the task, measure the quad axle's diameter and determine if you can adapt kart hubs to it or if it is easier to make a new axle either 1" or 1-1/4 inch and use kart hubs and wheels without any other problem. Also, check if there exist some kind of hub with the measurements that your stck axle has or if the stck hub can be modified. Many possibilities as you can see.

Edit: Btw, I spent around $230 on all the parts [axle ($30), bearings and carrier flanges ($25), hubs ($50), used rims ($45), tires ($60)] including shipping and custom paint. So it gets pricey but you will have something way different and most nobody has.

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CAM2

· #20 · Feb 22, 2013 (Edited)

JARYphoto said:
Your right Cam2. Kart rims would be ideal. The thing to look for when adding kart rims is the hubs. They come in a variety of sizes grouped in two main types of metric systems and determined by the axle diameter. They are either metric sized hubs or SAE hubs. Metric hubs are measured in millimeters and vary from 25mm up to 50mm (maybe more but these are the norm). SAE hubs are measured in inches and the most common are 1" and 1-1/4".

Wheels too come in two main different options, metric and American patterns. They use mostly three screws to mount on the hub. Metric pattern is usually a three hole on a 58mm circle and the center hole on the wheel where the axles goes through is 40mm in diameter. American pattern has three bolt holes on a 2-1/2" circle and center diameter of 1-1/4 (I think, can't remember well on the center hole).

I made an error and bought metric pattern wheels but had 1" (SAE) aluminum axle. Since hubs come either American or metric, not combined, I thought I was f'd up. But searching the web led me to bmikarts . com. They have hubs that adapt SAE axles with metric pattern wheels. Awesome product!!!

So when you're up to the task, measure the quad axle's diameter and determine if you can adapt kart hubs to it or if it is easier to make a new axle either 1" or 1-1/4 inch and use kart hubs and wheels without any other problem. Also, check if there exist some kind of hub with the measurements that your stck axle has or if the stck hub can be modified. Many possibilities as you can see.

Edit: Btw, I spent around $230 on all the parts [axle ($30), bearings and carrier flanges ($25), hubs ($50), used rims ($45), tires ($60)] including shipping and custom paint. So it gets pricey but you will have something way different and most nobody has.

Nice.I cant wait til youre done with the transformation........The barstool racer rearend axle kits work pretty sweetly too and I beleive a tad cheaper around $170 but good to hear your on a mission to make that thing as sweet as it can be..........Great job so far.........

I was on reserve about building one since MattO showed me the vid......LOL...I linked the vid to my friends and it seems they reminded me of Bald Hill........Its pretty lengthy with a nice downhill grade both ways from its highest point........Im going non-motorized but theyre all up for the action and the fun..............LOL...I dont think I can "up" my medical coverage but can still up my life insurance............LOL...LOL

I know how pricey the stuff gets......I still have oldschool vintage racekarts.....

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