DR177 kit installation

The original 2-stroke Genuine scooter and its 4-stroke manual and automatic offspring

Moderator: Modern Buddy Staff

Post Reply
User avatar
Mr.FixIt
Member
Posts: 141
Joined: Wed Aug 01, 2018 1:44 pm
Location: York, PA, USA
Contact:

DR177 kit installation

Post by Mr.FixIt »

Might as well start a new thread on this.

DR177 kit from Scooter Mercato came in Thursday. I spend all evening doing the cleaning and prep work to bolt the kit in. No grinding, no cutting, just bolt on. I remembered to measure how much stud was sticking up above the head joint, so I just threaded them back in the same distance and used the torque wrench to finalize the installation. Added enough 2T oil to the fuel tank for an extra pre-mix for run-in.

I managed to sleep all night with anticipation of kicking her back to life this morning.

It was that easy after I re-attached the SITO+ exhaust. I dropped in the 112 Main Jet to start with. She fired up with a nice bit of smoke from all the assembly lubrication. A quick twiddle on the idle mix screw and she's idling nicely. I triple-checked the timing.

I would have been alarmed at the noise from the new cylinder, but I watched a few videos where others experienced the same thing, and they said that the DR kit is just loud at first and will eventually seat in.

I wanted to go down to the post office, but it started raining so I didn't get a test drive in yet.

More to come when I get a few miles on...
Attachments
Kit in Box
Kit in Box
IMAG1393.jpg (23.59 KiB) Viewed 381 times
Page 1
Page 1
IMAG1394.jpg (66.51 KiB) Viewed 381 times
Page 2
Page 2
IMAG1395.jpg (123.37 KiB) Viewed 381 times
Eric
(aka Mr. Fix It)
User avatar
johnk
Member
Posts: 167
Joined: Mon Sep 03, 2018 9:42 pm

Post by johnk »

Nice work! I am really glad you got it working again.

I also like that the kit is "for agonistic purposes only."
2003stellaDave
Member
Posts: 74
Joined: Tue May 30, 2017 6:31 pm

Post by 2003stellaDave »

Cool. Keep us posted!
User avatar
Mr.FixIt
Member
Posts: 141
Joined: Wed Aug 01, 2018 1:44 pm
Location: York, PA, USA
Contact:

Post by Mr.FixIt »

Well, gang.... the rain finally stopped enough to do additional testing.

The 112 main jet was silly rich. It was just soot on the plug.

I skipped over 110 and went straight to 108. Still sooty.

I went down to 106 with a hint of soot, but not a lot of go. It burbled like it was too rich.

I didn't expect to go less than that initially, so I was faced with a quandary. I didn't want to jump the whole way back to a 100 main with nothing in the middle to tune with. So the only thing to do was increase the air. (I'm able to strip the main jet out with my eyes closed at this point)

I "de-blued" the stock air cleaner and discovered it was fairly contaminated with oil in the white part too. So I cut all of it off. (its an adventure right?) I had plenty of UNI air filter foam in stock, so that was fitted to the air filter frame.

Now with a free breathing air cleaner the 106 main jet hesitates ever so slightly like its too rich, confirmed by a hint of soot on the plug on a short ride. So I threw the 100 main back in and went around the neighborhood. With the free-flowing air filter, it seemed about right. Its still in break-in so I can't hit the revs and see how she pulls. It putters around reasonably, with only a hint of soot. The problem is running 3% oil for break-in contributes to an oily plug. I haven't gone for more than a mile or so on each of the final test rides, so she's really not up to temperature.

I'm certainly not going to call it a final tune. I might not even attempt "final tune" till I get a couple hundred miles into break in. Its close enough for today and I need a beer. For "agnostic purposes only", I think I'll just be skeptical enough to believe that it needs more testing and tuning. :P
Eric
(aka Mr. Fix It)
User avatar
Mr.FixIt
Member
Posts: 141
Joined: Wed Aug 01, 2018 1:44 pm
Location: York, PA, USA
Contact:

Post by Mr.FixIt »

Update.

The ride and tune testing continues on the DR177 & Sito+. As of today the present jetting is:

Stock 20/20 carb
55/160 idle, 160 air, BE3 atomizer and a 106 main jet.


4th gear and a good bit of throttle is just about right. Its still not broken in yet, so its not really peppy. I can cruise easily at 35-40mph on the flat. The 108 main jet was just boggy and wouldn't go.

Here's the issue. Part throttle just tootling down the road it has a burble to it. I don't know how to describe it. It hesitates and is not smooth. As soon as I add more throttle and she starts to pull it smooths out. Pulling the choke strangles the engine so its still not too lean.

Now I'm not sure what to change to get the mid-range corrected. :?
Eric
(aka Mr. Fix It)
Christopher
Member
Posts: 12
Joined: Mon Nov 11, 2019 3:36 am
Location: Rochester Minnesota

Post by Christopher »

Did you ever get the jetting figured out? Curious what you ended up with. I just bought a Stella with the same setup.
User avatar
Mr.FixIt
Member
Posts: 141
Joined: Wed Aug 01, 2018 1:44 pm
Location: York, PA, USA
Contact:

Post by Mr.FixIt »

The weather turned cold, so I haven't come to a final conclusion with enough miles for break in. It is between 106 and 108 Main Jet.

The 106 gives good pickup and pulling torque, but hasn't yielded a brown plug color. It does bog down when I pull the choke, so not overly lean.

The 108 seem a bit doggy in general like it is too rich. I'm considering a 107 Main Jet. If I drive by the Cylinder Head Temperature gauge, I can reach 280'F without really pushing hard (with this cold weather). That's making me think it might still be a little on the lean side, OR its still tight and not broken in properly.
Attachments
CHT
CHT
Screenshot from 2019-11-11 07-38-25.jpg (36.6 KiB) Viewed 329 times
Eric
(aka Mr. Fix It)
Christopher
Member
Posts: 12
Joined: Mon Nov 11, 2019 3:36 am
Location: Rochester Minnesota

Post by Christopher »

I want to try one of these, should be able to get a really good idea of the jetting for each stage.

https://www.plxdevices.com/PLX-Wideband ... -s/125.htm
User avatar
Mr.FixIt
Member
Posts: 141
Joined: Wed Aug 01, 2018 1:44 pm
Location: York, PA, USA
Contact:

Post by Mr.FixIt »

Its nice to be able to put a number on something and chart it out. The wide-band lambda sensors are power-hungry to keep the internal heater warm. I bought a system like this 15 years ago to try to measure the emissions of a natural gas Caterpillar G3406 engine that I was working on. The results were less than exciting. I ended up not using it, and it was an expensive failed experiment.

That's not to say that this newer unit wouldn't work. I imagine it would require fairly steady-state conditions to get a good measurement.
Eric
(aka Mr. Fix It)
Christopher
Member
Posts: 12
Joined: Mon Nov 11, 2019 3:36 am
Location: Rochester Minnesota

Post by Christopher »

I was thinking about feeding it with its own battery while tuning. Also need to hook up an.oscilloscope and see.how noisy the power really is. I could add a capacitor as a filter to the positive lead if needed.
User avatar
Mr.FixIt
Member
Posts: 141
Joined: Wed Aug 01, 2018 1:44 pm
Location: York, PA, USA
Contact:

Post by Mr.FixIt »

The #108 main jet was totally dogging on me last night when I took her out to the gas station for some Ethanol-Free. She didn't want to climb any hills. I put the #106 main jet back in which yields about the right performance.

So how hot should I let the CHT reading get (measured with the ring under the spark plug)? What's a good alarm threshold? Am I playing with fire exceeding 280°F and not really pushing it?

(edit)
According to http://www.vespalabs.org/wiki/vespa-tun ... ture-gauge
Roughly a Vespa engine will run at between 320F and 380F, different engine set-ups will run different temperatures

Apparently I have to re-torque the case bolts again, she's dripping gearbox oil. (grumble grumble)
Eric
(aka Mr. Fix It)
Christopher
Member
Posts: 12
Joined: Mon Nov 11, 2019 3:36 am
Location: Rochester Minnesota

Post by Christopher »

Those temperatures are about right, from my studying. I have been working on tuning my 50cc scooter with a 70cc big bore kit that turns 11,000 RPM. I've been using a cht gauge and shooting for around 320, I read to stop at 350.

This is where I get my information from.

http://49ccscoot.proboards.com
User avatar
Mr.FixIt
Member
Posts: 141
Joined: Wed Aug 01, 2018 1:44 pm
Location: York, PA, USA
Contact:

Post by Mr.FixIt »

Suffering from PMS (Parked Motorcycle Syndrome) as it is presently snowing.
I'm sitting here reflecting on the engine rebuild. I very much want to get out and get her broken in properly.

-------------------------------------

Night Flight

A red scooter is the best way to get around,
No other transport is finer that I have found.
A tank full of fuel will take you so far,
To visit with friends or hang at the bar.
After a dinner, its homeward we go,
Travel is pleasant its like we're on show.
Engine burble turns heads, like they've never seen,
So beautiful a cherished painted art scene.
My Italian-descended tibutation in style,
Nothing of late could bring such a smile.
A pinging was heard; whatever to do?
A loss of compression would surely ensue!
Darkness it came and I filled with dread.
It wasn't far to get back to the shed.
Coaxed up the hill giving all that she could,
The crest was ahead; I felt that we would.
Then plunged into darkness; nothing to see,
But a green lamp on the dash shining at me.
Off with the key and in with the clutch,
If I hit a tree, I'm sure it'd hurt much.
The whispers of wind was all that was heard,
The engine had died, and I uttered a word.
Word of complaint ruined my ride,
The headlamp was out! I could'a cried.
Some short distance more under the tree,
The moonlight provided little to see.
No push was needed; she showed such pride,
And that was the end of our valiant ride.
Attachments
Momento
Momento
73269695_2412267055495227_4358118536615297024_n.jpg (56.33 KiB) Viewed 245 times
Eric
(aka Mr. Fix It)
User avatar
Mr.FixIt
Member
Posts: 141
Joined: Wed Aug 01, 2018 1:44 pm
Location: York, PA, USA
Contact:

Post by Mr.FixIt »

It was 45 degrees in the sun today, so I got Stella out for some more miles and testing.

Even though the CHT reads some reasonable numbers (at these cool ambient temperatures), I'm still paranoid about the mixture. Here's the test I did today.

I ran out on a straight flat road in 4th gear and then pulled the choke out.
The engine neither improved nor faltered. So is this enough evidence to tell me that its still running slightly lean?
Eric
(aka Mr. Fix It)
User avatar
Mr.FixIt
Member
Posts: 141
Joined: Wed Aug 01, 2018 1:44 pm
Location: York, PA, USA
Contact:

Post by Mr.FixIt »

The 107 main jet was installed this morning. The results are noticeable directly in cylinder head temperature. On the usual test run route at temperatures in the 40's the CHT did not rise significantly. The worry was that with the 106 Main Jet that the CHT rose far too quickly and high with cold ambient temperatures.

The engine is still in break-in, so I can't expect full power.

Pulling the plug was not overly sooty. The 107 looks like a keeper so far.
Eric
(aka Mr. Fix It)
Patchik
Member
Posts: 4
Joined: Mon Feb 17, 2020 3:46 am
Location: Madison, WI

Post by Patchik »

Hello! I have similar setup on my 2009 Stella, bolt-on DR 177 from Mercato and the stock 20/20 carb, but with an SIP Road exhaust. Probably only 1000 miles since it was all put together. (No speedo hence no odo) But it has broken in by now.

Been trying all sorts of jetting setups over the summer and settled at 107/BE3/160 main with 38/120 idle jet. Anything above 107 felt like I was four stroking when holding the throttle steady, just smacking way too loud while cruising at 30 which cleaned up when opening the throttle.

The 55/160 idle caused me so many woes though. Never ran ok with that idle jet.

I ended up using a Euro air filter with the drilled holes, but then plugged the oval air hole that feeds the under the throttle slide. Paranoid about seizing when letting off the throttle at WOT I suppose. Heard Stellas have a lean throttle slide that provides extra air in the mid range for emissions or something.

Now I feel like I did something way too complicated, but I'm curious to see what works for yours. Mine seems accidentally perfect! But I'm swapping the carb boxes to deal with the 2T oil leaks so will re-test the jetting in a month.

Here for the examples for jetting the Stella with a 20/20 carb and a bolt on DR 177. Best of luck. May the winter break soon!
Last edited by Patchik on Mon Feb 17, 2020 6:57 pm, edited 1 time in total.
User avatar
Mr.FixIt
Member
Posts: 141
Joined: Wed Aug 01, 2018 1:44 pm
Location: York, PA, USA
Contact:

Post by Mr.FixIt »

That's what I need, a break in the weather. All the testing has been done at uncomfortably cold temperatures.

Patchik, thank you for sharing your experience with the idle jet. Its worth the effort to try a change there. I too have experienced issues with mid-range throttle with testing so far.
Eric
(aka Mr. Fix It)
Christopher
Member
Posts: 12
Joined: Mon Nov 11, 2019 3:36 am
Location: Rochester Minnesota

Post by Christopher »

Patchik wrote:Hello! I have similar setup on my 2009 Stella, bolt-on DR 177 from Mercato and the stock 20/20 carb, but with an SIP Road exhaust. Probably only 1000 miles since it was all put together. (No speedo hence no odo) But it has broken in by now.

Been trying all sorts of jetting setups over the summer and settled at 107/BE3/160 main with 32/120 idle jet. Anything above 107 felt like I was four stroking when holding the throttle steady, just smacking way too loud while cruising at 30 which cleaned up when opening the throttle.

The 55/160 idle caused me so many woes though. Never ran ok with that idle jet.

I ended up using a Euro air filter with the drilled holes, but then plugged the oval air hole that feeds the under the throttle slide. Paranoid about seizing when letting off the throttle at WOT I suppose. Heard Stellas have a lean throttle slide that provides extra air in the mid range for emissions or something.

Now I feel like I did something way too complicated, but I'm curious to see what works for yours. Mine seems accidentally perfect! But I'm swapping the carb boxes to deal with the 2T oil leaks so will re-test the jetting in a month.

Here for the examples for jetting the Stella with a 20/20 carb and a bolt on DR 177. Best of luck. May the winter break soon!
You can get slides with no holes and no cut outs on the bottom side from SIP scooter. I bought one and am waiting for warmer weather also. I figure a blank slate on the slide with the changes made won't be a bad thing.
Patchik
Member
Posts: 4
Joined: Mon Feb 17, 2020 3:46 am
Location: Madison, WI

Post by Patchik »

Edit to my previous post, I'm using a 38/120 idle jet.
User avatar
Mr.FixIt
Member
Posts: 141
Joined: Wed Aug 01, 2018 1:44 pm
Location: York, PA, USA
Contact:

Post by Mr.FixIt »

Hopefully shifting the mid-range to the leaner side through the idle jet and enriching the main jet back to 107 makes the difference. It certainly feels too rich in part-throttle as it is. If the SIP Road Pipe is similar to the SITO+ there should be similar results. There are a few steps in between the two jets according to the list of available jets. I have bigger main jets in stock as well so there is room for experimentation. Thanks for sharing your experience, Patchik.
The testing will continue....
I feel as if I have a small fortune invested in jets. :wink:
Attachments
SI Carb Idle Jets by Ratio
SI Carb Idle Jets by Ratio
IdleJets.png (8.82 KiB) Viewed 196 times
Eric
(aka Mr. Fix It)
User avatar
Mr.FixIt
Member
Posts: 141
Joined: Wed Aug 01, 2018 1:44 pm
Location: York, PA, USA
Contact:

Post by Mr.FixIt »

The saga continues. It was a balmy 70 'F today and the CHT was getting higher that I've ever seen it reaching nearly 300 'F on the way home. I wasn't even really pushing it hard. I had already been at a #108 main jet, which was spot-on at 40 degrees ambient this morning.

Changing to a #110 main jet didn't decrease performance measurably. #112 is too rich.

It got cool and dark again, so I stopped working on her for today.

Will the tuning never end!
Attachments
Warm Day Ride
Warm Day Ride
2020-03-09 19_34_21-Photos - Google Photos.png (175.16 KiB) Viewed 179 times
Eric
(aka Mr. Fix It)
Patchik
Member
Posts: 4
Joined: Mon Feb 17, 2020 3:46 am
Location: Madison, WI

Post by Patchik »

Nice! Well then I'm going up to 110 too. Will post my experience once that's in for the comparison.

Been riding in the city with small stretches so never had to put the 107 main to The Test. It handled some 2 mile highway stretches fine, but your temp change is good to know. Credence to my suspicion that I was running it hot at least. I have a cross state trip to make this summer to boot!


I realized that I was struggling with main jets before I installed that 38/120 idle and should've pressed further.

Do you have any 4-strokibg or bogging issues with the 110 main when you're coasting at 30 mph?
User avatar
Mr.FixIt
Member
Posts: 141
Joined: Wed Aug 01, 2018 1:44 pm
Location: York, PA, USA
Contact:

Post by Mr.FixIt »

I'm thinking the engine has to be well heat soaked. Quick trips may not be enough, and ambient temperature plays a part in reading the Cylinder head temperature.

I'm beginning to think the 38/120 idle jet is too lean in the mid range. The mix screw out 3 turns seems excessive. It doesn't bog at all part throttle, because it seems lean, and we don't want to risk a mid throttle seize.
Eric
(aka Mr. Fix It)
Christopher
Member
Posts: 12
Joined: Mon Nov 11, 2019 3:36 am
Location: Rochester Minnesota

Post by Christopher »

I have the same issue with a 55-160, using my AFR meter it is rich. I have a 45-140 on order. I'm running a venturi not a filter so my main jet isn't close to what you guys are using. I have a 122 main jet, according to my temperature meter and AFR meter the 122 main is about right if not a bit lean. When I get my leaner 45-140, I may need to up to a 125 main jet.
User avatar
Mr.FixIt
Member
Posts: 141
Joined: Wed Aug 01, 2018 1:44 pm
Location: York, PA, USA
Contact:

Post by Mr.FixIt »

Christopher, that's impressive that the venturi makes that much difference. viney266 in my local scooter club predicted that I'd be around 116 with my setup, but it doesn't seem that I can make any power with that rich a main jet. More power to ya if the venturi is passing more air and making happy torque. Is your case ported? I didn't do any grinding on mine, just slapped the kit on.

I actually went back to slightly richer with a 40/120 idle jet and it seems a little better. The idle screw is closer to 1.5 turns. I have been able to cruise mid-throttle without excessive CHT. She has more torque than ever before with this current setup. I tried richer main jets, but they just make full throttle boggy. Will warmer summertime temperatures really make that much difference? I want to try her again when its >70°F out before I pass final judgement.

(I write these down for myself as much as anyone else. I've changed jets so many times, I forget what's currently installed.)

Current setup:

DR177 and SITO+
Stock 20/20 carb
40/120 idle, 160 air, BE3 atomizer and a 108 main jet.
Stock air filter frame stripped and replaced with UNI foam.
Eric
(aka Mr. Fix It)
User avatar
BuddyRaton
Scooter Dork
Posts: 3934
Joined: Sat Sep 09, 2006 10:08 pm
Location: Boca Raton, Florida
Contact:

Post by BuddyRaton »

I may have missed it but did you chamfer the ports, check the ring gaps and retorque the head bolts several times after heat cycles?

While not a screamer the DR is a nice solid kit when done right.

Please keep us updated
"Things fall apart - it's scientific" - David Byrne
www.teamscootertrash.com

'06 Cream Buddy 125, 11 Blur 220, 13 BMW C 650 GT, 68 Vespa SS180, 64 Vespa GS MK II, 65 Lambretta TV 175, 67 Vespa GT, 64 Vespa 150 VBB 64 Vespa GL
Christopher
Member
Posts: 12
Joined: Mon Nov 11, 2019 3:36 am
Location: Rochester Minnesota

Post by Christopher »

Mr.FixIt wrote:Christopher, that's impressive that the venturi makes that much difference. viney266 in my local scooter club predicted that I'd be around 116 with my setup, but it doesn't seem that I can make any power with that rich a main jet. More power to ya if the venturi is passing more air and making happy torque. Is your case ported? I didn't do any grinding on mine, just slapped the kit on.

I actually went back to slightly richer with a 40/120 idle jet and it seems a little better. The idle screw is closer to 1.5 turns. I have been able to cruise mid-throttle without excessive CHT. She has more torque than ever before with this current setup. I tried richer main jets, but they just make full throttle boggy. Will warmer summertime temperatures really make that much difference? I want to try her again when its >70°F out before I pass final judgement.
I didn't do much to the cases, I did open up the transfer ports on the DR177 cylinder to match the case ports. I enlarged the boost port in the case by about 1mm in width to match the cylinder. I also cleaned up the exhaust port and polished it.

A venturi makes a big difference, I was around a 107 with a base stock filter also. I bought a venturi from shapeways, to give one a try. Vespa built a venturi into a T5 airfilter, the T5 had about as much power as a P200.

https://www.shapeways.com/product/ZFBJ7 ... arketplace

My current setup maybe a bit lean, haven't got to ride it with the change from a 55/160 which was rich to a 45/140.

Current setup:

DR177 and SITO+
Stock 20/20 carb
45/140 idle, 160 air, BE3 atomizer and a 122 main jet.
Venturi from Shapeways.
2003stellaDave
Member
Posts: 74
Joined: Tue May 30, 2017 6:31 pm

Post by 2003stellaDave »

How’s it going Eric? Do you have an update for us? What’s the difference from the stock setup? Top speed? Are you happy with it?
User avatar
Mr.FixIt
Member
Posts: 141
Joined: Wed Aug 01, 2018 1:44 pm
Location: York, PA, USA
Contact:

Post by Mr.FixIt »

No real update from my last post. Unlike Christopher, I haven't opened up the ports on the cases. The 108 Main jet still feels about right. There seems to be so many variables on engine builds that is is difficult to compare one scooter with another. Simple things like exhaust, intake, and porting seem to play the most significant role as I've compared to the work of others.

The cooler temperatures the last weeks hasn't allowed testing at summer conditions. The lack of any longer excursions during the current virus situation hasn't help provide any opportunities for places to go. The short trips to pick up takeaway meals, and takeout "beer runs" to the microbrewery has been the limit of travel. Until the engine gets properly heat-soaked in the summer, I'm maintaining the current setup without any real decisive conclusion.

She does seems to suck down the fuel at a greater rate compared to the stock Stella setup. I've always tried to run the same grade of ethanol-free fuel for consistency. The aim was "good reliability" without sacrificing too much economy. The important part is being able to pull up hills at the speed limit without having to drop to lower gears slowing down too much. I haven't reached 500 miles, but the engine has seen some occasional Wide Open Throttle pulls. The plug seems to indicate a nice neutral burn favoring the rich side without exceeding a CHT over 300°F. Mid-throttle response is acceptable. Engine starting is reliable especially when already warm.

I'm looking forward to the time when I can meet up with the local Three Mile Island Scooter Club for a reasonably long run. 8)
Eric
(aka Mr. Fix It)
2003stellaDave
Member
Posts: 74
Joined: Tue May 30, 2017 6:31 pm

Post by 2003stellaDave »

Cool. Thanks. ✌�
mondo1
Member
Posts: 23
Joined: Sat Apr 18, 2020 1:32 pm

Your emblem

Post by mondo1 »

Can you rell me where you got that italian flag hex emblem thats on your frony horn cover? I want one!
User avatar
Mr.FixIt
Member
Posts: 141
Joined: Wed Aug 01, 2018 1:44 pm
Location: York, PA, USA
Contact:

Post by Mr.FixIt »

Can you tell me where you got that italian flag hex emblem thats on your front horn cover? I want one!
The previous owner had de-chromed the Genuine badge and it looked pretty poor. I ground out the center of the badge till it was smooth with a Dremel bit and applied three strips of colored tape. Over top, I put a layer of Polyurethane "helicopter blade" tape to secure everything in place.

I assure you it looks better in a photograph. I've been holding out for a proper one.
Eric
(aka Mr. Fix It)
User avatar
Mr.FixIt
Member
Posts: 141
Joined: Wed Aug 01, 2018 1:44 pm
Location: York, PA, USA
Contact:

Post by Mr.FixIt »

ARGGGGG the saga continues.

The ambient was 80°F today and I rode the 9 miles into the office and back. (Running the 107 Main Jet at present, due to lack of power and noticing some "four stroking".)
She goes "waaahha hah hah hhaaaaahaaaa" when the engine is still cool, and has flat spots where she doesn't want to go.

Stella didn't really find a happy place until I got on a long stretch of flat road running around 40mph with a CHT just touching 300°F.
At this point I was part throttle just cruising, and I could change throttle positions and maintain a good "weeeeeeeeeneeenneeeee" sound.

I have no deposits around the threaded metal portion of the plug, and the level of soot seems to be about right burning off to brown color. There always seems to be oil at the edges of the plug.

Should I be trying a hotter plug? (Presently running the standard B7HS)
Or should I just drop the main back to 106, where it was BEFORE the DR cylinder kit?
Attachments
Plug
Plug
2020_05_26_20_47_14_plug.png (134.92 KiB) Viewed 77 times
Eric
(aka Mr. Fix It)
mondo1
Member
Posts: 23
Joined: Sat Apr 18, 2020 1:32 pm

Post by mondo1 »

Ive tuned my kawasak 2 stroke with chambers and only had to go up 2 jet sizes. Considering the stock jetting for the 150 is like 94 I would think that going down one size would not hurt a thing. My DR kit will be installed with a 105 main along with the 45-160 idle jet. I do live in Florida so I know it may even be rich. I will see in about a week when the rain stops. Your plug does looks good so I would try a full throttle run with the new jet and shut it down. Read your plug. It should be OK. Keep us posted with your results.
mondo1
Member
Posts: 23
Joined: Sat Apr 18, 2020 1:32 pm

Post by mondo1 »

What I meant to say is that the 106 main should be OK
mondo1
Member
Posts: 23
Joined: Sat Apr 18, 2020 1:32 pm

Post by mondo1 »

My idle jet is 40-120
2003stellaDave
Member
Posts: 74
Joined: Tue May 30, 2017 6:31 pm

Post by 2003stellaDave »

A “colder� plug may be better. B8HS.
mondo1
Member
Posts: 23
Joined: Sat Apr 18, 2020 1:32 pm

Post by mondo1 »

I dont think a colder plug would eliminate his flat spots. It may make them worst, but for the price of a spark plug it may be worth a try. Just my 2 cents.
Post Reply