[jjmaine]

So I bought the bike a few years ago from a guy who had just gotten it, laid it down on the left side and gave up on motorcycling. When I got it the left handlebar and shift pedal were bent so I replaced them. Now that I have the fairings off I notice that the front of the engine got tweaked toward the left in the rubber mounts.
I tried loosening that engine mount and tapping it back into alignment but it wouldn’t budge.
I wonder if I should just leave it as is )since I’ve put 6,000 miles on the bike and it doesn’t seem to be a problem) or taking the exhaust off so I can get a jack under the engine to loosen all of the engine bolts and re-tighten them in the sequence that the manual says.
Not sure if those rubber mounts are deformed and I’ll cause more issues by trying to fix it but the OCD in me thinks I can’t let it go because I know it isn’t as it should be lol.
Can that top mount be removed with the engine still in the bike so I can replace the dampers? If the entire engine has to come out then that will settle it for me. It can wait until it becomes an issue. What would you guys do?
Excuse any typo’s, the keyboard on my phone is tiny lol
Would it work to loosen all of the engine mount bolts without having a jack under the motor? I know it isn’t the right way to do it but I’m thinking that even if you bolt the motor with the engine supported, over time everything must fall down and rest on the bolts anyways?

 

[SparkyMJ]

Hmm. If you look at the exploded parts diagram for engine mounts, it appears that the inner cushion is just a length of rubber that the front engine mounts just sit and can slide on a tad. All to say, it's probably fine and was probably always like that. You shouldn't ever have to un-tweak motor mounts from a drop.

That said, the other rubber dampers on your valve cover bolts look pretty bad. You might be in a dry and/or sunny place that promotes rubber deterioration. My 300 has over 56k miles on it, and I just now (despite my last track crash that I still need to repair) the engine mounts are starting to wear out enough that vibrations are now being transmitted a bit more into the frame. So I may replace my engine mounts, and I could share what they look like when I get them out eventually.

I think you are fine so long as the engine is secure, you don't feel excessive vibes, and you can get a proper chain alignment on the front sprocket.

-Mike

 

[jjmaine]

Thanks Sparky! I was hoping you would see this and comment as I recently saw your engine rebuild thread so I know you have experience taking the engine and installing it. Oh yes, the o-rings on the valve cover are dried out and also the cylinder head gasket has some cracks. I've ordered all new ones including the spark plug hole gaskets. Those gaskets under the valve cover bolts are $8 each lol. What a scam.
Do you think maybe my engine moved when I loosened the nut on that mount bolt? I never loosened the rear bolts. I tried getting my jack under there before I loosened it but couldn't get a good purchase with the exhaust on so it just wanted to move the entire bike on the stands.

 

[jjmaine]

From looking at my bike, it looks like it would be fairly easy to pop them top mounts off and replace those engine damper bushings? When I took the nut and large rubber/washer and looked at the end of the left bushing it was clear that the bottom is squished (from the weight of the engine). Also since many of the other rubber parts are dried on my bike.... Now would be the time for me to do it while it's apart and I've got plenty of time. And I know myself, it's going to eat at me all winter and I'll end up replacing them anyway lol.

 

[SparkyMJ]

I saw you read my thread, hope it helps! Thanks for reading.

Can't go wrong with replacement man. You sound like me; if it's bothering you now, it will bother you more later. I haven't tried jiggling the motor without fully removing it, so I am not sure how hard that will be, but on my engine removal thread I did mention how 'wedged' in my motor was. I bet that's just how they sit in there, so you might have a hard time jostling it around even with all the hardware loose.

Worth a shot. I am in the same boat as you, except I want to replace mine due to potential wear, not just them seating oddly. If I can't replace them without dropping the engine, I probably won't do it.

I guess I didn't think about it, but the front engine mount has that hinged piece. Maybe take that out, clean the bolts and check that piece for any warping after the drop. I don't think you'll find anything suspicious, but if you're going to get in there anyway, might as well.

Who knows, you might get the mounts off and see all the other parts too, and it might all look totally fine. If you get in there and don't find anything truly broken or worn out, I wouldn't bother replacing parts. Reassemble per the shop manual and maybe do the typical 'reseat' of the motor in the frame that so many people talk about, and you'll probably be golden man.

Hope this helps.

-Mike

 

[jjmaine]

I did this same thing last winter with my dirtbike. By the time I was done I had replaced EVERY seal, bearing, wear item and the entire top end of the motor (piston, cam, cam chain, valves etc.). When I added everything up it made me sick lol I can't help myself, if I see something not quite right I'll have to fix it or get it fixed.
That's what I was thinking. Losen everything up and try to straighten it and if the mounts look okay I'll leave them for now.
FYI, the only place I could find new oem engine mounts for the Ninja 300 was Rocky Mtn. ATV. They had 4 in stock and I bought 2 of them. If you need some it may be worth getting them while you can as some new oem parts are getting harder to come by. Maybe some other place has them in stock but I couldn't find anywhere else.

 

[jjmaine]

And by the looks of it, if I leave both rear bolts tight and support the engine with a jack, I think I can unbolt the radiator and take those engine mounts right off and replace the dampers. I can let you know how it ends up going...

 

[SparkyMJ]

Thanks for the heads up on the parts availability. I don't think Im in a big rush, so I will probably wait. Usually PZ has what I need, they just take a bit to hunt down the parts if they're not "in stock".

I've been sitting on my crashed 300, maybe it's time I dug it out of the corner and put my eyes on it again today. Been working on my GSXR for the past couple months.

I'll check my mounts to see if they are at all similar to yours. Who knows, maybe mine will look the same. Do keep me posted on what you find.

-Mike

 

[jjmaine]

Will do. I can see how the little Ninja might get neglected if I had a big bike as well. Prices on used bikes in my area have been absurd the last year or two. I'd love to find an older 600 that needs some tlc for cheap.

 

[SparkyMJ]

Anything big four and uncrashed is a decent bet. Best if the engine starts. That was how I got my gixxer. Found it in a lady's yard, in awful condition. Fried wiring, dash didn't work, starter button was shorted on, scratched and dinged, bent wheel. But the motor would fire up, and I didn't hear any horrific noises, so I bought it. Took about 7 months to get it where I want it, and it rides like a dream. Mid 2000's is a great era if you're looking for a 600 needing TLC. Winter is upon us, go hunting! Bet you could find something ugly for 1k or less.

I did order my head stand pin to get the 300 back in the air, so progress shall be made!

-Mike

 

[jjmaine]

Dang, I wish you could find a bike that cheap in my area. I'm sure the deals do come around but you have to be right on top of them before they sell.
Nice, get the 300 fixed up!

 

[motopreserve]

Little late to the party - but I can confirm that leaving the back 2 bolts in and placing a jack under the front will allow you to loosen the front bolts. Actually, the rear bolts will hold it pretty well on their own.

But you’d need to lower the front end to fully remove the “triangle” mounts up front. IIRC, there may be rubber mounts on the inside and outside of the triangles??? I could be wrong about that.

I just came across some billet hard front mounts for the ex300 on Spears. Seems people like the more direct feel on the track. Might look into machining some next time I have the motor off for measurements. Curious if it would be a noticeable difference, or just a negligible change for the folks with deep pockets.

 

[jjmaine]

It looks to me like I would be able to unbolt the radiator/fan and swing that out of the way (hanging by zip-ties) and then I could remove the mount that connects the engine to the triangle mounts? That should give the clearance to drop the triangle mounts out of the top of the frame? Of course I’ve never done it so I may be completely wrong.
Going to remove the exhaust today and both brake systems to disassemble/clean them.Still waiting on lots of stuff, gaskets etc.

 

[motopreserve]

Might work. But those triangle mounts need to come down quite a ways. I’m not sure if they will lower far enough with just the other part swung down. I was removing the whole engine every time - so I’m not positive.

Good luck. It’s not particularly difficult. Just annoying compared to other motors I’ve removed/installed.

 

[jjmaine]

I was just getting ready to reply that I'll give it a try and see how it goes but I think I just got a better idea. Maybe I can just remove the mount off the engine and replace those dampers without taking the triangles off the bike. With the bolt removed and the inner mount gone, I think those dampers should tap out easy enough.
Anyway, first I'm going to try loosening all of the engine mount bolts and straighten the engine. If that works I'll probably wait until later to replace the dampers.

 

[jjmaine]

So, after all of my waffling and faffing around, I loosend all of the engine mounts up and made sure the engine would wiggle happily in the frame with most of its weight resting on my jack. Tried fiddling with the top mount to see if it was out of line but it honestly seems fine and didn’t want to move even with the engine loose and floating. Like Sparky said, it very well could have came like that from the factory. I’m sure when they are assembling these they don’t stop and back up if something is a few mm’s off lol.
Anyway it seems happy so I torqued them all back up. My lower rear mount snapped and crackled as I torqued it so I might replace the bolt and nut just for peace of mind, they’re cheap. It snapped and crackle when I loosened it as well. Also the rubber dampers actually appear to be in fine shape so I’ll save the new ones I ordered until I need them.
It seems a useless waste of time but at least I can rest easy knowing I did what I could to make sure it was right. And the top rear engine bolt was not torqued correctly (not sure what it was but not even close to 51ft lbs.) so at the least I caught that.
Thanks everyone for the input!

 

[motopreserve]

I can verify that the nuts and bolts on this bike snap and crackle more than any bike I’ve ever worked on. It was disconcerting at first. But after the first 472 times it happened, I have sorta become used to it

Well done checking the rubber mounts off the list. Why spend energy worrying about a possible issue when you can know for sure with very little effort. That’s why I’m only somewhat frustrated (but still frustrated!) with the issues I’ve had on this bike. I’ve now had my hands on almost every part of it. And by the time I’m done, I will rest assured that I was the one that tweaked, torqued and fixed the most crucial parts on the bike.

 

[jjmaine]

There's nothing better than learning how to work on and fix your own bike. Then you know if something breaks you can fix it. No way I'm paying a shop to do something I can do at home. Nothing a few youtube vids and a quick chat on a forum can't fix.

Good to know about the crackling bolts. It made it hard to feel my torque wrench click but I got it. The nut would crack and then slip forward 1/4 turn. Jumped the hell out of me, I've never had that happen when tightening a bolt. Loosening I've had them crack loose with a loud snap.

 

[motopreserve]

There's nothing better than learning how to work on and fix your own bike. Then you know if something breaks you can fix it. No way I'm paying a shop to do something I can do at home. Nothing a few youtube vids and a quick chat on a forum can't fix.

Good to know about the crackling bolts. It made it hard to feel my torque wrench click but I got it. The nut would crack and then slip forward 1/4 turn. Jumped the hell out of me, I've never had that happen when tightening a bolt. Loosening I've had them crack loose with a loud snap.

I’m really not sure what the deal is. Because I cleaned all the bolts on a wire wheel before I reinstalled them. So there was no old loctite or gunk that should have caused the sounds. But it has been fairly constant on many bolts, of various sizes. Particularly the larger bolts. You should hear the internal bolts that cinch the head onto the jugs. That sound made me think I had cracked the block!

 

[jjmaine]

I hate that kind of thing. Makes me think “jeez should I take the bolt back out and re-torque?” I did it once and it made the same racket so I guess it sounds like it’s normal and no need to replace. I didn’t remove the bolts but the threads on the bolt and in the nut looked perfectly fine