Compression relief valves

Looking for help! 2000 twin cam 88 bored to a 95. Put in 2.7v starter, 80 tooth starter ring gear. New HD battery! Still starts hard, especially cold weather with temps in the 40's.
So here are the questions. Big Boar Battery with 350 cold crank amps? Compression relief valves, or both? At what compression ratio do you neee the relief valves?
I cant believe that a 95 kit would create that much cylinder pressure. I would assume the compression ration isnt even 9.5 to 1.

Any thoughts are greatly appreciated!
Bob:witsend:

Is your ignition good & timing right?

My 100" engine with 13:1 compression fires right off with a stock starter. It does have Zippers compression relief valves in the heads, but have rarely used them & they're only good for 2 revolutions of the flywheels anyway - the one for each cylinder pops back up after the 1st compression stroke.

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last summer I had it dyno'd so I believe so. running stock carb smooth bored with larger jets. bike starts when we have been out riding all day. let it sit a day, then try starting it when it is cool, no go. i always have to have the battery tender on it. checked the battey and stater tonight and both are good. i did order a big boar 350 cold cranking amp battery today and checked all connections. looking good.

havent had a compression test, probably should! When I hit the starter button for the first time, it engages trys to turn then stops. Release the button then push again and it will turn over. If it dosent start in the first few rotations then the battery is not strong enough to try again. It does spin slow at first the spins normal after the starter gets going.

You may have a current drain (short) somewhere & finding that will require more than just checking connections. Also, a fairly common problem is battery cables corroding inside the insulation where you don't see it, cutting down on the current available to the starter.

Havent thought about the battery cable corrosion in the middle of the cable. It would be worth changing. Every year I clean and inspect all the connections i can. I did do a leak or drain test, all was fine. These are great ideas, thanks. I will invest in new cables today and put them on tonight! I'll let you know the results.

Just ordered a compressiont tester. can anyone tell me where to find the spec on what the compression results should be? This guage only tells preasure not compression ratio.

Also the cams I put in are Andrews 510.
Dyno results were 93 HP & 99 foot punds torque.

I should also have mentioned spark plug wires - they can break inside the insulation & you won't see it. Grab one bare-handed while the engine's running & you'll darn sure feel it though !

so do you know what your Static compression is ? to much or to little can cause a motor to start hard or run bad Its not compression ratio its stactic compression

go to page 22 in the Andrews Product catalog and its on line Yes its the Andrews products that make the cams and tranny gears or call a tech there 847-759-0190 central time

changing parts, without knowing if there the right combanation Common mistake ! but it happens all the time

i will check all the connections tonight. had to order the battery cables. my buddy has a compression tester to loan me so i will test that tonight. i will also look up the static compression. thanks a million for all the help!!!!

cool, i will check out the all balls starter. not apposed to replacing the starter again if it solves the problem.

hey who did the work you know machine work and assembly? ....instead of changing and doing this and that to all the parts talk to somebody that knows what hes doing....meaning dont talk to a Harly Dealer there all parts changers! they know less then small rock ! Call Andrews Products in IL or Randy in Iowa @ king of cubes.com

when you do the compression test follow the guide lines on page 22 in the Andrews cam catalog they walk you through it on what to do and theres a chart of what the pressure reading are telling you! if its around 145 to 165 its good for a modified street motor and it will be hard to start! over 185 and you need compression relese set up and it will really be hard to start plus 110 octane + but it should never be that high unless its a monster race only motor over 10.5 or higher C R
165 to 185 thats a reading for big motors like 120 +cu in and it will be hard to start....detonation and over heating can occure

read that info page before you do to many things buddy!
If you understand what a motor does , or is doing, and what it can do, then you have learned something! Ask , read ,learn! then do !

Thanks 59panhead,
I bought all the parts myself, had the heads machined, ported and polished and assembled it myself during the winter of 98 with the help of a good friend who is a gear head. You gave me some kickass ideas that I'm going to do tonight.
Thanks!
Bob