Tuesday, 2 December 2014

Aluminium cake

I've had numerous cake shaped pieces of aluminium delivered before, most get turned largely into swarf  and this one was no exception. This one was destined to become offset sprocket bearing holder. It took a lot of hacksawing to cut it in half partway through.

This was preceded by top yoke manufacture.....

Sunday, 30 November 2014

The blog without a subject

A little over 7 years ago i started this blog when i bought my first dragbike which i named the bopchop. With work now well underway on the 3rd dragbike I'd started to run out of space, and so i decided that i needed to rehome the original bopchop.
I didn't even get chance to post on here that i was looking for a buyer. I mentioned it on our facebook page on Wednesday and by Thursday it was sold. Only the rolling chassis, no engine or electrics. And today, it was collected by it's new owner.
Hopefully it will be out again before too long, which is something that was unlikely to happen if i kept it anyway.

And so, here is a concise recap of the bopchop!
As it was when purchased in 2007
One full rebuild later and ready to race 2008
Open Sport Nationals at Shakey 2008
At the extreme bike weekend 2008 the bopchop did what i never imagined it would when i was rebuilding it. It ran the into the 8 second zone with an 8.87 at 150mph
By the middle of 2009 it was running fairly consistent mid 8's and the best time it recorded was an 8.33 at the National finals, and a best terminal speed of 158.36mph

And finally - here it is today, ready for a new home and an engine transplant!

Saturday, 22 November 2014

On the bottle

Team Bopchop are pleased to announce that 'On the bottle' will be supporting us next year. Providing discounted nitrous refills, nitrous parts and VP race fuel. On the bottle will be at most rounds at Shakey next year as well as selected Santa Pod events. More details of the events they will be attending, and their full product range including full nitrous kits for cars and bikes, as well as bottles and parts can be found online at http://www.onthebottle.co.uk/
Or take a look at their face book page - Mark Onthebottle, and tell them you heard about them here. https://www.facebook.com/profile.php?id=100005443099052&fref=ts

Sunday, 16 November 2014

The cellar thing

It came out into the daylight for the first time today. It even fits out through the cellar door... phew!

Saturday, 8 November 2014

Go with the flow

At the end of every race season i nearly always have a plan to not change much on the bike, as usually it was just starting to run pretty good by the end of the year. It would make sense to cover it up with a sheet, change nothing and carry on where we left off. However, that never happens, something always appears or get offered to you at a good price and you end up changing lots of stuff.
Only this year thats not the intention. The bike went well all year, with the only improvement  being the 60ft times and the MPH. It went 7.5 at the first event of the year and never went much quicker.
And so the intention this winter is simple - to make it faster.

The priority at the moment is to sort the problem with the clutch. The engine is out of the bike and partly stripped down. I'm not 100% sure what the problem is just yet, but it seems that the primary gear on the clutch basket may be bent. It's an odd part to get damaged in that way, but it has a fair amount of side to side runout.
The focus after getting that sorted is to upgrade my nitrous system. I've always used the small NOS 16080 powershot solenoids, and they've worked really well, however they only flow so much especially at the low fuel pressure my pump delivers, and i've reached the limit of what they can deliver. And so, i have a plan to carry on using the small NOS fuel solenoid but to double up and use two of them. Each one feeding just a pair of cylinders this time rather than all 4. This also means i can position them really close the the fogger and pretty much eliminate the fuel line from solenoid to fogger. The long lines i'm fairly sure are the cause of the lean spot i've talked about in the past.
The nitrous solenoid will be replaced with a new Nitrous Express one, and i've gone for one that should be pretty future proof, a 15300L with a .125 orifice that can flow up to 500hp of nitrous.

I've also decided to go with the flow where the new bike build is concerned. I was hoping it would be finished for the start of next season, and it may well still be. But there's still a long way to go and i simply don't have the funds to go out and buy all the remaining parts brand new. I have to wait for bargains to appear, and i want it to be right. If that means it's not done then so be it, and i can't help but think that it's no disappointment to have to run the old bike for a few meetings or even the whole season as it's running so well and has loads of potential left in it. Especially with a better nitrous system that i can perfect on it before transferring it to the new bike.

And talking of the new bike, today was spent making the rear brake caliper hanger. The caliper is off a 250 Aprilia scooter so comes with a mega long brake hose and a left hand side handlebar lever. It saves a lot of hassle making a rear brake foot lever, was fantastically cheap, and will be easier to use.

Tuesday, 21 October 2014

Destruction prevention

Amazingly the Extreme bike weekend was yet another race meeting run through to completion, but not for us.
Saturday started with rain but by midday the track was dry and we managed to make 4 qualifying runs before the track closed. The last run being my favorite as it was run in total darkness which adds a heightened sense of speed in my opinion! There was a strong headwind all weekend which seemed to be knocking a few mph off most peoples top speed. We were were down 5 mph on average, but we still managed to qualify first and ran a string of pretty consistent runs.
Q1 7.7224166.69mph
Q2 7.7575167.93mph
Q3 7.6907167.28mph
Q4 7.6919167.28mph
Q5 7.6638168.53mph

This put us in good stead as there were only 6 bikes entered and if we won the first round there was a bye run in the next, taking us straight to the final.
It wasn't to be though, as just before we were called for the first round i spotted a problem with the clutch, it looked like a damaged bearing or loose hub nut. I stripped it down checked everything but couldn't find the problem, even after swapping out the bearing and some spacers it still wasn't right and so we made the decision to not risk damaging the whole engine and to not make anymore runs.

It didn't change the outcome of the season anyway, as Allan Davies went through to the final and took the event win, making him APIRA, SPRC and ACU Champion, so congrats to Allan - we had some pretty epic races towards the end of the season. And i took the Runner up position in all 3 championships as well.

Thoughts have already turned to next year. We may change and run in the funnybike class, especially if the new bike is ready. However, i do have the option of staying in Competition bike, and it is a great class that needs the numbers. So we'll see. Maybe season 8 will be even better than the rest....

Tuesday, 14 October 2014

All to play for

Coming up is last race on the 2014 ACU calendar - the Extreme bike weekend at Santa Pod.
Two championships will be decided at this meeting, both the ACU and Santa Pod racers club championships. Alan Davies has the points lead in both, but i'm not too far behind and it is possible for us to take it. The SPRC championship being the most desirable as the prize is free entry to the Santa Pod rounds next year.
A summary of all the possible bike class outcomes has been posted on eurodragster.com and can be seen HERE
There are 6 entries in comp bike including one newcomer (to comp bike at least).
4     Phil Crossley         Suzuki GSX     1500cc
5     Tony Clark         GSX1100     1500cc
8     Kevin Osman         Hayabusa     1300cc
15     Paul Hambidge         ZX12R         1200cc
16     Dave Smart         GSX 1300R     1300cc
42     Allan Davies         Suzuki GSX     1428cc

The bike is ready, it hasn't required much attention, clutch servicing and valve clearances, and  a general going over looking for loose bits. I decided to further modify the progressive graph on the controller as the recent experiments to eliminate the lean spot have been quite successful, and so i've taken out even more nitrous, dropping it down to just 20% at one point. If that still isn't enough then i can work on the fuel graph and have that increase momentarily before resuming the progressive build. Tyre pressure will be hopefully be the other area of experimentation at the weekend, finding out how high we can go before it stops working, and seeing if we can get the 60ft times down a bit further. 1.15 is the best so far.

I did some more Bronze welding at the weekend and got the last of the engine mounts welded on, plus front subframe mounts. Fork shortening has also been on the menu, travel has been reduced by nearly 50mm, and i chopped up some FZ750 springs which will be added to the rather soft 125cc ones to make them a bit stiffer. They can also be preloaded should they not be firm enough.