Low Compression on new 125cc Stroker ??

[Hppowdercoatings]

I've had it running through a few heat Cycles on the E85 but could not get a smooth idle. I changed jetting a bunch and air fuel mixture but idle won't stop surging from like 1700-1950 Rpms.
So changed out the Fuel to Castor 927/93 octane 32:1 mix. Still runs same way, tried jetting range from 150/48 up to 165/65. Still has the idle surge and bogg when you give more then 1/4 Throttle.

Basics.
125cc
Castor 927/93 Octane 32:1 mix
30mm PWK
Jetting 160/60
NGK Bp8hs plug .25 gap

One thing I never checked was the Compression, so I went ahead and checked it multiple times cold and warm.
Here is pic of Compression Reading with it Cold. Best of 75-psi
Multiple checks warm was a best of 90-psi

Manual says stock reading should be 114-171 psi

Question to you builders out there , what to check before I tear the motor Apart ?
Thanks for any help ..

[ped]

Hi Hp, rent a new compression tester @ autozone . sometimes the testers go bad and give a faults reading.

[Downsouthdio]

Start jetting down..those seem too big

[Downsouthdio]

Also run an ngk7..also when checking
COmpression..pull the throttle full throttle while kicking and checking for the compression

[LMH]

Sounds like air leak.

[swimmingfree]

LoveMyHonda is wright it a air leek i wood gess the head ..
swimmingfree

[Hppowdercoatings]

Update.. Removed head to check bore/piston/rings and gaskets . All looked good , but the lower paper CyL to block gasket looked a little iffy so I replaced it and reassembled head . After Buying a new Compression Tester I retested Compression 5 times and she was reading about 125-psi. Runs 95% better I just need to do some more Jetting changes. Currently at 155-50. Idles a lot better.
Once I get it broke in and good Tune it should Run like a Raped Ape.. Took it up the street for a short heat cycle and with only 1/4 throttle it wanted to Wheelie....lol

[Hppowdercoatings]

awesome! I'd personally bump the compression up to take advantage of the E85. The beauty of E85 is less change of pre-detonating. I've been wanting to make the switch on my turbo car for quite some time. only problem is cold starts. It's terrible in the winter.

I'm going to Run it on 93 octane 32:1 Mix for a few miles to get it broke in, then Bump the Compression and Switch to E85..

[swimmingfree]

E85???? i think you will have to up jet with e85 gas...
swimmingfree

[Red Eft Performance]

Hello be careful with that 50 pilot jet. That's really small even with regular gas.

Keith

[Downsouthdio]

If you can..try to use a temp guage

[Hppowdercoatings]

If you can..try to use a temp guage

Not a Problem , running a Trail tech Vapor to keep track of all the Vitals..

[paulpauly7]

is e85 race fuel? we call it avgas here and isnt easy to get unless you have a regested race licence or own a plane .I have neither lol

[Hppowdercoatings]

In USA You can get E85 at Regular Gas Stations. In my state, Missouri there are about 138 that carry it.
It's 85% Ethanol 15% unleaded gas and a Rated Octane of 105-108..

[LMH]

In st Charles area there's more than in St. Louis. Especially St. Peter's or ofallon. Do you do powder coating? I'm going to have some guy in Fenton do a bunch of stuff for me I'd rather give a fellow board member the money.