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Message started by Bjarras on 10/19/15 at 12:41:31

Title: Won't rev over 3000 rpm and misfires
Post by Bjarras on 10/19/15 at 12:41:31

Hello guys,

I'm new to both this forum and also as a Savage owner.
My name is Björn, lives in Gothenburg Sweden and English is not my native tounge but i'll d my best to be understood :o

I just bought this bike as an Project. The bike had an broken Engine and was quite dismantled. Luckily, my friend had an running Engine to spare so the last couple of days now I've been puting them together.
But i've run in to some Engine trouble;

The Engine only revs to about 3000 rpm and it sounds like it's misfireing.
it will not get past these 3000 rpm.
The old bike that had this Engine had the same problems and different CDI:s, sparkplugs, petcocks, ignition coils and carburetor has been tested without it being solved.

As I see it, there is only 2 reasons left that I can Think of.

First is the valves (intake/exhaust). Perhaps they needs to be adjusted.

Second is the ignition. Is it possible to adjust the advance/retard on the ignition maualy? I can't find anything about this in my Clymer manual.
Or can the ignition plate only sit in one way and the CDI will do the adjustment automaticly?

Or am I missing something obviuos?

Also worth to mention is that the bowl vent hoses on the carburetor is not attached. But as I have understood it shouldn't matter.

// B

Title: Re: Won't rev over 3000 rpm and misfires
Post by verslagen1 on 10/19/15 at 13:12:14

Welcome B,

There are a few things that will limit the engine to 3000 rpms, air, fuel, electrical and mechanical... did I leave anything out? ;D

Mechanical, if the cam has been off, possibly it wasn't timed right when it was put back in.
electrial/mechanical, when swapping engines, the right CDI must be used. The timing between a 4 and a 5 speed are different. Use the right CDI or swap rotors.
Timing otherwise usually is never an issue.
Fuel, Too lean main or clogged will do it too.
Air, clogged air filter? No air filter?

Bowl vents are normally open, usually we have tubes attached to make the only higher.

Title: Re: Won't rev over 3000 rpm and misfires
Post by Ed L. on 10/19/15 at 15:42:35

Start with the simple stuff, check the petc0ck by putting it in reserve and clamping off the vacumn line going to the side of the carb.
The sensor location for the ignition is in a different location with the 4 and 5 speeds. Instead of swapping the rotor try swapping the left side cover where the sensor is mounted. I would think it should work but has never tried it. You will need to use the different starter gears that came with the side cover you are using.
A bad high voltage coil could cause the problem but by reading your post you have already swapped one out.
Try to find out what was done to the engine before you got it. It might give you a clue as to what to look for.

Title: Re: Won't rev over 3000 rpm and misfires
Post by Bjarras on 10/19/15 at 22:35:06

Hi,

Thanks for the answers.

This engine is a -94 and my chassis (incl. CDI) is from -92 so I don't Think the CDI is wrong for the engine. My friend bought a new CDI to match the engine but it ran like this anyway.

The engine has been mounted in 2 different chassis with each chassi having their own equipment like ignition coil, carburetor and so on.
But "changing" Everything outside of the engine has not helped.

So I'm quite convinced that the problems lies inside the engine it self.

I don't know if the cam has been out but it's worth checking if the timing is correct.

But regarding the ignition, is it possible to adjust it underneith the left engine cover. Don't know the correct name i'm afraid, but I Think it's called the ignition plate which on many engines can be turned to advance/retard the ignition. Is this possible on the Savage?

// B

Title: Re: Won't rev over 3000 rpm and misfires
Post by verslagen1 on 10/19/15 at 22:45:49

left side is the stator cover.
the timing sensor is mounted with a screw in a hole.
some have sloted it, but you only get a couple of degrees adjustment.
don't think that'll do you much good.

Title: Re: Won't rev over 3000 rpm and misfires
Post by Bjarras on 10/19/15 at 23:35:28

Well noted, ignition is not possible to adjust and is probably then not the problem.

But if we go back to the cam. I've read the section about the cam in the Clymer manual but I can't find any guide on how to check the cam timing. Do you know if there is a guide available at this forum for this?

Many questions I know, but I really apreciate you help guys. :)

// B

Title: Re: Won't rev over 3000 rpm and misfires
Post by Steve H on 10/20/15 at 03:53:47

If the carburetor has not been swapped with a known working one, check the needle in the slide. The spring should be below the clip pushing the needle up not above pushing it down.

Title: Re: Won't rev over 3000 rpm and misfires
Post by verslagen1 on 10/20/15 at 07:18:24

http://suzukisavage.com/cgi-bin/YaBB.pl?num=1256079122

http://www.hunt101.com/data/500/medium/cam_line_up.JPG

Title: Re: Won't rev over 3000 rpm and misfires
Post by Bjarras on 10/23/15 at 04:00:54

Back again after some wrenching and now I really need some help with what I'm doing from you engine gurus :)

I've removed the left engine casing and I'm not sure how it should be :o

I don't understand how you attache multiple images in one post so there will be 4 posts with these images of the rotor mounted on the engine

Title: Re: Won't rev over 3000 rpm and misfires
Post by Bjarras on 10/23/15 at 04:05:27

Pic 2:

Title: Re: Won't rev over 3000 rpm and misfires
Post by Bjarras on 10/23/15 at 04:05:50

Pic 3:

Title: Re: Won't rev over 3000 rpm and misfires
Post by Bjarras on 10/23/15 at 04:06:15

Pic 4:

Title: Re: Won't rev over 3000 rpm and misfires
Post by Bjarras on 10/23/15 at 04:14:06

The Engine is put in TDC and as you can see on these images the rotor has some scratches on it and the "welded piece" on the side of the rotor that the pickup reacts from is approx 3" long.

Due to the condition of the rotor I can most certainly say that someone has been working on this rotor Before.

The markings on the rotor is:

72
6601
F3T434

But I also have the old Engine for this bike, please see Picture below.
That rotor is totally unharmed and the welded part to which the pickup reacts is only approx 1" long.

The markings on this rotor is:

71
2901
F3T434

Everything on the bike (As CDI, coil etc) is original from the "old" Engine.

Can it be so that someone sometime has changed rotor on the Engine that won't rev above 3000 rpm and has mounted the wrong rotor?

I would really appreciate some help in this matter since I don't know what the differences may be.

Thank you in advance.

// B

Title: Re: Won't rev over 3000 rpm and misfires
Post by Steve H on 10/23/15 at 07:11:29

If there is a difference in the pickup area on the rotor, I would say change the rotor to match the CDI that you are using.

We didn't get from '89 to '94 in the States, so we aren't for sure what year it changed but we are aware that there are differences in the 'old' and 'new' ignition and when changing engines between the 'old' and 'new' you have to change the rotor to match the ignitor box.

Some of the more knowledgeable guys will be by soon. If I have said anything wrong, they'll correct me but I believe I am right on this.

Hope you get it sorted soon.

Title: Re: Won't rev over 3000 rpm and misfires
Post by verslagen1 on 10/23/15 at 07:50:11

I believe you're right, the difference between new and old is the length of the welded piece. I noticed it, but didn't register which is which. Will have to look at it when I get home.

Take a look at the starter upgrade in the tech section index.

Title: Re: Won't rev over 3000 rpm and misfires
Post by Bjarras on 10/27/15 at 07:33:16

Success!

Bike is running fine. I changed the rotor to the one on my broken engine.
Once the rotor and the CDI matched it started right up and ran perfect.
Unfortunately I didn't have the flywheel remover tool so I made one my self that worked fine.

Now it's only all the rest left to do...

// B

Title: Re: Won't rev over 3000 rpm and misfires
Post by Art Webb on 10/27/15 at 15:49:15

Congratz! hopefully all the rest will be easier