italjet dragster 180 new owner with lots of questions
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2010 gts 300 super. 09 MP3 500 lite
Joined: 02 Apr 2013
Posts: 741
Location: tampa
Sun Apr 25, 2021 8:16 am quote
purchase a dragster 180 needing alot of love. I have two stroke questions.

bike has 180 cylinder running malossi phbl25 carb. it starts and idles great. it goes great midrange and wot. its needing tuning in light cruise area. very bubbly . may just be lightly clogged pilot jet as bike has likely not been used much in last few years. need to clean carb first and inspect jets before any tuning can take place. but all that is not my concern.

my biggest concern is the bike is prelube. which is not acceptable to me. I want to return the bike to autolube. the tank and pump are still on the bike. I have spent about three hours trying to figure out exactly what parts I need to source.

the phbl frpm malossi can be purchased autolube or premix. I cannot find pics of the difference. nor can I find the info if premix carb can be converted to autolube.

I tried finding pics of a stock setup. that would be helpful. would love to see how the cable to operate pump originally operates. that basically where I am stuck. how to get a second throttle cable to the pump. what are my options? I can fabricate quite well.

second question is what two stroke tuning books are best? was gonna start with graham bell book? or is there a better first book.

Molto Verboso
2007 Stella 225
Joined: 02 Nov 2019
Posts: 1683
Location: Rochester, Minnesota
Sun Apr 25, 2021 12:56 pm quote
I think you'll find another port for two stroke oil on the autolube setup. I was playing with a 50cc scooter and went with a larger two stroke carburetor. Among other things the two stroke version has an oil port.

The oil pump was run from a second cable connected to the throttle.

Last edited by Christopher_55934 on Mon Apr 26, 2021 2:35 am; edited 1 time in total
Too Many piles of Junk that need too much work and too much money
Joined: 06 May 2019
Posts: 628
Location: Roseburg, Oregon
Sun Apr 25, 2021 10:57 pm quote
Congrats on the new score! I've always wanted one of these, since they first hit the streets!
2 matching N.Z. '69 VBC Super, 177cc Racer, VespaCross Bodge, Puch SRA150, Piaggio Zip 100! & others
Joined: 26 May 2013
Posts: 4028
Location: That bushfire place
Thu Apr 29, 2021 6:47 am quote
"my biggest concern is the bike is prelube."
which is not acceptable to me. ....

Toughen up... you get no sympathy here sookin about prelube !
2010 gts 300 super. 09 MP3 500 lite
Joined: 02 Apr 2013
Posts: 741
Location: tampa
Thu Apr 29, 2021 7:44 am quote
its all good. I know there are die hard pre lubers around these parts. wasnt looking for sympathy. I ended up ordering a nice alloy splitter for the throttle. I will be making my own throttle cable. I want to try a thumb throttle setup on this bike. I have been toying with the idea of thumb throttle on all my scooters. I have lots of seat time on jet skis and gopeds. I prefer thumb throttles and have no clue why they arent more popular among bike/scooter circles. I will be returning bike to prelube. I prefer my engine get 200 to one at idle and 20 to one at full throttle. 35 all the time is great for race bikes. this is a street machine.

my other immediate changes will be to the air filter and suspension tuning. the air filter makes the bike terribly loud. and the filter is far too small for our dusty/sandy roads. so I will be either ordering a stock box to modify or I will be going custom with a box design of my own. I like QUIET. i have no use for loud additions to any of my machines.

the suspension needs refinements. bike is brutal in the comfort department. first three changes: ditch the new michelins. they are rough riding tires compared to what I like. as luck may have it I can run the same tire models I have on my amazing helix build. shinko s007 front, kenda 425 rear. next will be setting up shocks to ride better. I will remove the solid mounts and add isolators. then I will taylor spring and rebound settings to suit a more compliant ride.

I dont have a much ride time yet but I wanted to comment on how unique the front suspension is. pushing bike around it feels like a sub 200lb scooter. riding at 40mph the bike goes dead stable. bike has a tiny 11 in wheel in front and it feels like a heavy 16. not kidding. and the narrow bars dont help. it needs muscle to weave bike back and forth. it has the opposite of fast steering. the second notable is how much I like a trailing arm front as opposed to a traditional twin tune setup. you get much less brake dive on a trailing arm setup. well this SIS has zero dive. and I mean zero. it fells like you are driving a two by four frame around. great for smooth flat roads. not so great when things go technical.

she oozes with character. thats for sure. I like it. new challenges afoot.
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