1972 DS7 The Row Boat

Great looking bike! Who doesn't like a red bike?

Highly recommend you think about investing in a cheap strobe light and gain certainty of your ignition timing. It is not a case of how well it runs, but whether or not you melt holes in your pistons. Very common for people to report how great their bike was running just before . . . . Ignition timing is more critical than jetting to prevent disaster - though jetting usually gets the blame more often. Usually it take both, but no amount of over jetting the mains will overcome too much advance.

Once you do that and the bike starts and stays running reasonably well (seems like you are already there (once you determine the flooding issue)), just get the main jets right. You probably are wasting your time on anything else except deciding on which style of needle jet/emulsion tube you want to use. All the drivability tuning can come last. Do it the other way around and you may find yourself starting over (again!) after you find you need different timing and/or mains.

Thanks Teazer.
JP I'll define try look into a timing light. Should on at the auto store work?
You're saying to start jetting the top end or 3/4 throttle on up first then go down to 1/2 then 1/4?

I like to get the bottom end close so I can start the fool thing and get moving. Then it is important to get WOT high rpm right and after that worry about midrange. If you try to play with the main jet to get it rideable, the WOT setting is unlikely to be close and that will bite later - either through poor performance or worse.

Go up a long way from stock. You may be surprised what a large main jet it needs .

I dropped a 200 main in there to get it richer to be safe. Most of what I've read leaned around that on mains. Clip is in the middle position right now. The 200 seemed rich when I rode it last. I'll verify timing then get the air screws to function properly. From there I'll start at wot.

Any high intensity gun style automotive strobe timing light will work fine. The light doesn't know it is being connected to a motorcycle - is simply blinks the strobe light on when it detects the plug being fired. It can be a really cheap one, you don't need anything fancy. Really cheap ones do not have an inductive pick up, so you have to plug a "T" connector into a spark plug lead, which should come with it. Actually on your bike, you probably will need to make an extension for a plug wire anyway, as the factory lead is so short it is very hard to get an inductive pick up on it. You will need to check the mzb for timing marks so you know what you have. Probably the easiest way is to put in a dial indicator and either see what is already on the mzb or make your own marks that align at the timing you desire. Then just rev it up to whatever rpm you want to check the timing at, check with the strobe and adjust accordingly. Hopefully the mzb will have the correct timing but it pays to be sure.

Like Teazer says, jet the mains for Wide Open Throttle. That is JUST WOT, not 75% to 100% - just wide open. The reason is that at anything less, you will be running on the (presumably) more restricted needle and needle jet. This insures that, at least at WOT you will not be lean. Unfortunately it is still possible to be lean at part throttle openings if the needle/needle jet is too restrictive, but you aren't asking for max power at part throttle, so injuring your engine is vastly less likely.

I put a timing light on it to check the timing. It was firing at 2.5mm BTDC as per MZB. I found out that that was Euro spec timing so I went back to yamaha factory settings at 1.8mm BTDC.
The overflow was caused by the float pins somehow getting on top of the float arm. It seems very difficult to mess this up since the float guides are on the bowl and the float arm is on the carb itself. You have to put the floats and bowl on from the bottom up so I don't know how this happened. It was visible once the bowl drain plug was removed, regardless it is now corrected.
The air screw is now functional and increases RPM on the bike at idle. The lean bog is still at <1/4 throttle and the highest rev at idle came in at 1/2 turn out. I'm going to go up on the pilot again to try and get the idle circuit set at the Yamaha spec of 1 - 3/4 turns out on the screw.

Good job on the timing light. When you set the timing to 1.8, what rpm did you use? Do you have any info on an advance curve with the MZB?

Edit: Just looked up the MZB iggy - evidently no timing curve so you should be good to go!

They make a programmable controller for it. I need miles on the bike before I even think of that. I did the checking by myself so I couldn't look up at the tach while twisting the throttle to get the rpm. As your query turned up, there is no curve.

Just wanted to post up that I finally put some miles on the bike this evening, about 30 to be exact. 958 days after I brought the bike home she is street legal!
I had to pull the jet needle out and clean that off then she ran fine. I can now do plug chops on the bike. It was kinda cool to look back in the rear view mirror and see my riding buddy in a cloud of blue smoke. Lol. Have a great weekend DTT!

Congrats! Great feeling to be moving, no? I just finally got 30 miles or so (in a row!) on mine last Monday...

Yeah man I saw the pics you posted. Looks like some rad scenery. On a rad bike.

I put more miles on this weekend. I put 200 mains in and she pulled to 9K pretty easily. I have a 32.5 pilot in right now and the air screw is 2-1/2 turns out which is telling me it's still too rich. I know stock was 25 and I can't see it going that low with the Y-boot and chambers. Hopefully this weekend the 30 will be the one.

I know it has been a few months since you posted but I have a question. First I have read your entire thread and awesome job and congrats on the BOTM for January nomination.

Second how did you decide on the angle to mount the top mount of the Ninja Suspension where the top of the shock bolts to? I have a Ninja 250 swing arm and rear linkage along with a GSXR shock I am thinking of mounting up on my RD350 just like you did and I cant seem to find how to do the top mount at the correct angle or length. Thanks.

If you answered that in your thread (and I some how missed it) you can just post the post number and that works for me. Once again bad ass bike. Really like it.


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Thank you for the kind words. The angle at the top Mount was dictated by the angle of the bell crank. The bell crank needed to be parallel to the floor so from there I set the top mount. I missed the mark on the first try and had the bell crank in a stiffer spot of its stroke. Getting the bell crank angle correct made a huge difference in the suspension. Good luck with the swap and hit me up if you need help.

Awesome that is exactly what I needed to know. I will let you know when I need help. Your thread has been a huge inspiration for my build.


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Cool man. The bell crank should wind up being 90 deg. to the shock also. This way it will put full force on the shock.

A nice long build and you brought that beauty to Barber. Hell of a bike man.

Then I just put in a little gas and go! Lol

clem said:

Cool man. The bell crank should wind up being 90 deg. to the shock also. This way it will put full force on the shock.

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Awesome. I also saw you put in a brace for the shock to mount up to that went all the way across the frame instead of the piece that just stuck out like the stock ninja. Did that make it easier to mount or was it just for added strength.


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When I readjusted the bell crank, the shock was lowered from the first position. With that, it put the shock closer to 90 deg. to the upper mount. That was when I decided to extend the upper mount similar to an RZ350 frame as Teaser suggested.