1.3:1 Roller Tip Rocker and Drop Gear
Turbo Mini Forums

I am getting to the final stages of my 998 build and have two main question that I’m finding hard to answer with the Search tool.

One is what rockers do most people run? To me it looks like the best would be 1.3:1 Roller Tip Rocker, but seam to very hard to find? The next being pressed steal oval pad Rocker with offset bushes. So what the go and where would be the best place to get the Rollers?


The second being Drop Gear, what straight cut gears do people run with 998’s? Swiftune are the only ones I’ve found that say they are for a 998. Are the Primary gears different between 1275 and 998? Finally are the roller idler bearing a lot better or not worth the extra money?

Thanks in advance Nathan.

you using a 940 or small bore head?

roller rockers (regardless of ratio) are a nightmare to find for small bore heads, nick swift might have a few old sets in his parts bin, but dont count on it

"Turbo's make torque, and torque makes fun"

"did you know you can toast potato waffles?"

Yes it's a 940 head, there are some more specs and pics in "Show Us Yours! > Slo998 build".

I'l send Nick an email.

Thanks Nathan.

nathan, minisport at padiham sell these give them a ring, also the timkin SC idler is worth every penny go for that set, available from minispares north ask for richard......... £300 mark for the set

drop gears are not available at MS for small bore Steve, afaik swifty is the only guy with them 'on the shelf'

"Turbo's make torque, and torque makes fun"

"did you know you can toast potato waffles?"

min-its said they have some being manufactured as we speak not the r/b type, 2-3weeks, dident say a price though.

We have the same issue at the moment. Only Swifty has the small bore primary. But the roller bearings are overkill IMO.

Bushing a large bore primary is a good option. Has anyone had this done?

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

www.twin-turbo.co.uk

i will have a word with richard or neil at minispares north see if the are going to sort some ?

Thanks for all the replys it looks like Ill be putting an order in for the Swiftune A+ Roller Bearing Drop Gear Set for a 998. Seems like it would be to much stuffing around re fitting a 998 bush back in a 1275 primary gear.

Ive found a set of oval pad press steal rockers so will probly use them with offset bushes to 1.35:1. After some calls and emails to the big suppliers in the UK Minisport UK is the only one currently that do a roller tip 1.3:1, but there is still some questions about their longgevity and Titan do Full Rollers (tip and shaft) in 1.3:1.

Can people see a big problem not using roller tips with stainless steel valves and Bronze valve guide, as in wear rates from the side loading of a conventional rocker?

Thanks Nathan.

Swifty sell a loating bush to allow fitment of a 1275 primary onto a 998 crank. I assume this si the only difference between his small and big bore kits

On 12th Nov, 2009 Paul S said:

I think Gary OS has taken over my role as the forum smart arse

not quite gary

those swiftune bushes are specifically designed for theyre own primary gears and are not oe repro's

ask me how i know!

"Turbo's make torque, and torque makes fun"

"did you know you can toast potato waffles?"

How do you know?

texted 118 118

"Turbo's make torque, and torque makes fun"

"did you know you can toast potato waffles?"

Ah, is that why they are a pain in the tits? I got a 998 one believing it would be a simple fit in my 998 crank and primary. It turned out that the OD was way too big. Myself and Paul then turned it down so that it would fit. We just assumed the OD was to match up with a 1275 primary.

Well I guess that just proves that assumption is the mother of all fuck-ups

On 12th Nov, 2009 Paul S said:

I think Gary OS has taken over my role as the forum smart arse

yeah the swiftunes are designed be held in with a circlip, and the od as you say is larger

there is no difference (as far as i am aware) between 998 and 1275 primary gears (beside the ratios of course), just different bushes used.

"Turbo's make torque, and torque makes fun"

"did you know you can toast potato waffles?"