I have been building links with a specific anchor text for a few months now on and off ' Motorcycle Helmets ' . How ever when i search for that in G my site is no where there. I haven been successful with ' motorcycle parts ' and ' bike parts ' but can't get the other keywords that I am shooting for. What can I do!. BTW i am pointing to a landing page on my site, not the parent domain.
By landing page do you mean a page that is not really linked to from your main domain? Like an affiliate landing page? Google does not like these types of pages. They have Quality Raters who are constantly looking at the SERPs for particular keyword, country, language combinations and if they find a thin affiliate site or affiliate landing page showing up in the SERPs they will rate it as irrelevant or spam causing it's rankings to fall way back in the SERPs. Basically, they bury you... You may want to check out this official Google document (http://www.mauriziopetrone.com/blog/wp-content/uploads/quality-rater-guidelines-2007.pdf)that was leaked a year or two ago. Interesting reading and gives a lot of insight to how Google views pages. It also will give you an idea of how Google can bury a page that their Quality Raters stumble upon or how they might bury you (penalize) you if reported for spam and they conduct a manual review.
PS: Hopefully you are not using the exact same link text for all of your inbound links you are building. You need to vary the link text around the phrase you are trying to rank for. If Google sees 1000 inbound links and every one of them is for "motorcycle helmets" then they likely see that as a signal that the links were not obtained naturally. If you're trying to rank for "motorcycle helmets" then I suggest that you link mostly with the phrase "motorcycle helmets" but also link with phrases like "motorcycle helmet" (singular), "helmets", "helmets for motorcycles", "helmet for a motorcycle", "helmet", etc. Vary the link text while including the keywords "motorcycle", "helmets", "motorcycles", "helmets".
Canonical makes some good points. I was going to mention that you need to vary your link anchor text. Your homepage likely has far more links than your helmets page. So it is understandable that you have achieved rankings easier for 'motorcycle parts'. Your website is also more optimized for that phrase. You start every page's title with 'Motorcycle Parts'. That makes it obvious that your entire website is themed around motorcycle parts. It also creates a lot of relevant links....links from pages that have your target phrase right in the title. It helps to have your target keyword closer to the beginning of your page title. Your helmets page doesn't have much unique text either. The only unique text gets repeated on the product info pages. Motorcycle helmets may simply be a more competitive keyword. For a phrase like that you are competing with every helmet manufacturer and every store that sells helmets. I'm sure there are a lot of companies that specialize in only helmets.
Check your tags again and make sure they are relevant to the content in the landing page. That could be a reason why it's not ranking.