FED UP WITH VIBRATION!!

[PorterzCustomz]

I replaced the bolts with grade 8, stocked them down with locktight it was a nite and day difference. Now, many offroad hours later I get the vibration back again.. I cannot stand it, the plastics rattle really bad and it just feels awefull. You cannot see the engine move but the vibration is unbearable. The bolts were still tight so I took off the front cradle mount to figure out what was going on. I could not believe what I had found. The mount is paper thin, the bolts are starting to pull thru the mount because its so thin!! The mount is about .050 thick. I can hold the mount in one hand and bend or twist it with just my grip. The problem is the mount not the bolts, it bends and twists so the bolts can never hold tight. I am completely fed up with the paper thin mount system that lets the engine vibrate and rattle everything on the bike.

I have decided something has to be done. I am going to try and make new mounts from scratch using strong thick metal that wont vibrate twist and bend. I may also finish making the frame complete for more strength and to take out the flex. If you ever take the skid plate off and look at how the frame was never completed you will know something is very wrong. It looks like there are 4 mounting holes on the very bottom of the engine that can be used as a 3rd mounting plate to further hold the engine that they where suppose to use to secure it but never did because there is no frame work on the bottom. I think this is another part of the problem the engine is not resting on anything, its just basically hanging and dangling from the top! unreal... Well im going to see what I can do.. Wish me luck, I will need it, it looks kinda tricky because if you finish the framework on the bottom it has to be able to be unbolted because thats how the motor comes out. I looked at it for about 1/2 hour and I think I know what I want to do..

It will take me at least a few days to design and fabricate the new mounts and perhaps utilize the bottom engine mounting area that is not used while at the same time finishing the frame and it has to be strong and unbolt-able kinda like the front subframe on a car. :roll:

http://img210.imageshack.us/img210/5458/holeox4.jpg (http://imageshack.us)

i feel your pain dude. I have the same problem and mine is the counterbalanced motor. it seems like when i tightened the bolts that helped for a while but now the vibes are back bad enough to numb my hands. I was thinking about trying to drill out the 3/8"?? holes to 7/16 and put in larger bolts.

if and when you come up with a way to fix this problem, let me know because I would be interested in purchasing one of these modified brackets.

until then I am going to start at square one and replace the bolts but when i put them in this time I am going to put rtv around all of them.

when my engine shifted in position (im assuming that is what happened) and my vibes started real bad, I was convinced my tranny was going out. i think now its safe to assume that the vibes are due to the lack of a frame. who knows.

good luck and keep us posted.

[red2003]

Wow, that mount is spent. It looks like the metal broke out, not wore out. Looks like that bolt was very tight. I think the lower sub frame is a good idea for strength, but I don't think it's the source of your vibes. The 83 / 84 Honda XR200R that these bikes are copied from has the same exact engine mounting system and they were smooth as anything. The Roketa's, like mine, have the same frame as your Lifan and they don't vibrate at all. I think it's a Lifan specific problem. I haven't heard of any other brand bikes vibrating. At cruising speed, 55 - 60 mph, my Roketa is amazingly smooth, especially for a single cylinder thumper. I gotta believe it's a Lifan thing. Maybe we should start a poll about it and see if it is effecting other brands too??

[AZ200cc]

Wow, that mount is spent. It looks like the metal broke out, not wore out. Looks like that bolt was very tight. I think the lower sub frame is a good idea for strength, but I don't think it's the source of your vibes. The 83 / 84 Honda XR200R that these bikes are copied from has the same exact engine mounting system and they were smooth as anything. The Roketa's, like mine, have the same frame as your Lifan and they don't vibrate at all. I think it's a Lifan specific problem. I haven't heard of any other brand bikes vibrating. At cruising speed, 55 - 60 mph, my Roketa is amazingly smooth, especially for a single cylinder thumper. I gotta believe it's a Lifan thing. Maybe we should start a poll about it and see if it is effecting other brands too??

My bike was pretty dang smooth, If You got high into the RPM range You would get a little vibe but nothing that would make You want to get off the bike...So I would agree it might be a Lifan thing.

[TeamCheap]

WOW I wonder if that is the same bracket thickness as whats on ours, I'd guess they are but I have put probably 300-400 hard trail miles on mine since the rebolt.


I still think about making the engine protection bars that mount where that bracket mounts and then runs under the engine and mounts to the frame under the engine near the pegs.

TC you may already have done this but could you detail how you did your rebolt?

[TeamCheap]

Yeah it's been done over and over.I'll see what I can remember off the top of my head. :lol:

First of off all I used was a large drill bit set-many drill bit selections-a center punch-an electric drill and sockets & wrenches (didnt use the air gun it doesnt need that)

I started first by finding a drill bit that would fit the largest hole of any given set of holes.A set of holes would be one (1) engine mount bolt.

Example :lower rear engine bolt-first I determined which of these holes were the largest-then I found a bolt that I felt was RIGHT-very little wiggle room but enough to slide the bolt thru or maybe have to tap on it LIGHTLY-then slide the bolt thru all the holes seperately if the bolt didnt fit then drill it(remember I'm still on that lower rear bolt location) and using the drill bit that fit the largest hole exactly I drilled out any smaller holes to make all the holes in a given location the same-then set the bolt in snug but not tight-that comes at the final tightening.

I did the two large rear bolts on mine first then I moved up to the four front bolts and got those set and used washers wherever I could get them to fit and lastly I did the top three hole set of bolts and by this time the two three hole brackets didnt come close to lining up so I just whipped up a set.
That four hole front bracket is a bit of a joke as I recall.

first I tightened all the other six bolts.
Then I made the brackets very fast and accurately simply by placing a piece of paper over all three holes (2 frame & 1 engine) and using a pencil I just went back and forth and found/marked the exact hole locations-once I had a template I found a piece of flat stock and held the paper on it and using a center punch set the holes carefully then drilled them out-my bike and engine didnt need the little spacers but my wifes bike still needed them as hers still had the stock engine and I just used some washers to shim it.

If I were to back off the nuts on all my engine mount bolts a My engine wouldnt wiggle around very much at all.

As I put the new bolts in I would snug them up, not TIGHT just snug so the next hole would be set with the last one sort of holding position and so on until they were all in.
Once I had all the bolts in I did a final tighten by hand just using wrenches and sockets.(an assistant helps here)

I'll be ripping the engine out of the wifes bike soon to do the top rear engine brackets the right way and I'll try to snap some pics of how hers held up to the rebolt and the stock long bolt.

[TeamCheap]

You know porterz I havnt seen a messed up hole like that one on the bracket yet.

Did you have silicone or anything on that also?
it does look like it was tightened down a bit much but that hole looks like it was cut with a torch. :lol:

[PorterzCustomz]

You know porterz I havnt seen a messed up hole like that one on the bracket yet.

Did you have silicone or anything on that also?
it does look like it was tightened down a bit much but that hole looks like it was cut with a torch. :lol:

nope, no torch, it does look a little like that but it was the mount vibrating around the bolt. The part that looks like its burnt is just the paint that was flaking off from the vibration. I did not use silicone and yes I did sock it down with brute force but I made sure just to use a socket wrench so it was nothing crazy. If you took the mount off and realized how flimzy and thin it really is you would understand how it started to pull thru, I can bend and flex it with my HAND!!

Here you can see better in this picture this is the inside. If you look close in one of the holes you can see a chunk of metal that wore away and you can see how the vibration caused the bolts to eat away the holes and the mount to rub the case causing even more wear.. Plain and simple, very thin soft metal.. You can also see the leftover locktight red, there was no reason for them to come loose except alot of vibration and the thin mount.

http://img501.imageshack.us/img501/1230/chha0.jpg (http://imageshack.us)
http://img501.imageshack.us/img501/1230/chha0.12771e5296.jpg (http://g.imageshack.us/g.php?h=501&i=chha0.jpg)

[katoranger]

I am interested to see what you come up with for a cradle.

Allen

thx tc

[PorterzCustomz]

I am interested to see what you come up with for a cradle.

Allen

Yea, so am I. So far its proven to be a pain in the ass but when its done this thing is gonna be be one strong solid cookie! A lot of measuring, cutting, grinding, drilling, welding exc. When I realized I could bend the stock mount with my fingers I knew anything I could make would be stronger. I am also adding a bottom engine mount and completing the bottom frame. When im done I will work on the top mount under the tank but im guessing that one will be easy.

[fatboy250]

The Roketa's, like mine, have the same frame as your Lifan and they don't vibrate at all. I think it's a Lifan specific problem. I haven't heard of any other brand bikes vibrating. At cruising speed, 55 - 60 mph, my Roketa is amazingly smooth, especially for a single cylinder thumper. I gotta believe it's a Lifan thing. Maybe we should start a poll about it and see if it is effecting other brands too??

My OHC is smooth also. HOWEVER, my push rod does have vibe issues. So, I wouldn't say it's a Lifan issue. I think it's a push rod engine issue!!

[katoranger]

Top mount should be easy as TC explained above.

BBR makes cradles, but they are spendy.

Allen

[red2003]

The Roketa's, like mine, have the same frame as your Lifan and they don't vibrate at all. I think it's a Lifan specific problem. I haven't heard of any other brand bikes vibrating. At cruising speed, 55 - 60 mph, my Roketa is amazingly smooth, especially for a single cylinder thumper. I gotta believe it's a Lifan thing. Maybe we should start a poll about it and see if it is effecting other brands too??

My OHC is smooth also. HOWEVER, my push rod does have vibe issues. So, I wouldn't say it's a Lifan issue. I think it's a push rod engine issue!!

Hmmm, well maybe we need a pushrod / OHC poll then. Or maybe both!

[PorterzCustomz]

**UPDATE**

Fabrication is coming along nicely, I found out the key to the vibration. I am able to bend and flex the front frame rail that hangs down by the front tire with my arm!!!! That's why it vibrates, the front frame is not complete because its not boxed in and its not holding the motor steady along with the thin mounts. I was so shocked to see that I could flex the bar with very little effort!! I almost made a video to show you, I may still.

[fatboy250]

Really, is this with the engine still bolted in tight? If not, it could be because the engine is a stress member to our frames.

[PorterzCustomz]

Really, is this with the engine still bolted in tight? If not, it could be because the engine is a stress member to our frames.

This is without the engine connected. Having this design with a motor that is prone to more vibration is the issue. The fix would be to finish boxing the frame, replace existing mounts with thick strong mounts and take advantage of the bottom engine mount as a resting place for the motor.

[PorterzCustomz]

ALL NEW SUPER HD MOTOR MOUNTS MADE, FRAME NOW FULLY BOXED IN, 0 VIBRATION!! JUST GOT IN FROM A 8 HOUR ON/OFF ROAD TEST!! INCREDIBLE!! PICS & MORE INFO GOING UP TOMORROW..

[SpeedSouth]

ALL NEW SUPER HD MOTOR MOUNTS MADE, FRAME NOW FULLY BOXED IN, 0 VIBRATION!! JUST GOT IN FROM A 8 HOUR ON/OFF ROAD TEST!! INCREDIBLE!! PICS & MORE INFO GOING UP TOMORROW..

Would it be too much to ask you to post a link from this thread to the "PICS & MORE INFO"?

I went out of town and now see a thread where you're running your bike at 90mph, when the last I knew it was in bits waiting for stronger mounts.

I looked and failed to see another thread in this forum. Did you move it elsewhere or not post pics?

I thought this thread was the place to get this information, but I guess not? :? :? :?

[PorterzCustomz]

ALL NEW SUPER HD MOTOR MOUNTS MADE, FRAME NOW FULLY BOXED IN, 0 VIBRATION!! JUST GOT IN FROM A 8 HOUR ON/OFF ROAD TEST!! INCREDIBLE!! PICS & MORE INFO GOING UP TOMORROW..

Would it be too much to ask you to post a link from this thread to the "PICS & MORE INFO"?

I went out of town and now see a thread where you're running your bike at 90mph, when the last I knew it was in bits waiting for stronger mounts.

I looked and failed to see another thread in this forum. Did you move it elsewhere or not post pics?

I thought this thread was the place to get this information, but I guess not? :? :? :?


****** http://chinariders.net/modules.php?name=Forums&file=viewtopic&t=4008 *****

[SpeedSouth]

Thank you! :D

[justinkr58]

I have hi bird 250, with locktite all around, and silicone in stead of the gorilla glue it was great the vibs are 70% gone but at hwy speeds 70 mph it puts my but ahnds and feet to sleep.
i have an OHC 250cc

[kczukiman]

I have hi bird 250, with locktite all around, and silicone in stead of the gorilla glue it was great the vibs are 70% gone but at hwy speeds 70 mph it puts my but ahnds and feet to sleep.
i have an OHC 250cc
I know what your talking about but we have to remember,they are one lungers and they are going to vibrate.I havn't seen one that hasn't.