Theses starters do tend to be sluggish. I would suggest you check all electrical connections are clean and making good contact. I would also suggest to refurb your starter motor. I also strongly recommend going for a different battery such as the mottbat one. There are plenty on ebay. They cost double or so the price of a lead acid type but physically are the same size and DO give out much stronger power when starting and also seem to hold their charge better. Ive left mine over 7 months and it has still started on the button
Cheers
KK
